user471: According to this article by Ven. Dhammavuddho Thero:

Majjhima Nikaya 55 ..... The Buddha denied this, adding “Jivaka, I
  say that there are three instances in which meat should not be eaten:
  when it is seen, heard, or suspected (that the living being has been
  specifically slaughtered for oneself) … I say that there are three
  instances in which meat may be eaten: when it is not seen, heard, or
  suspected (that the living being has been specifically slaughtered for
  oneself).”

And another quote from the same source:

Anguttara Nikaya 8.12 ..... This is one of the discourses which clearly
  shows that the Buddha and his monks ate meat. Also, we see that meat
  from an animal that is already dead when it is purchased is allowed to
  be used, but not if the animal is alive.

In summary from the above and various sources:

It is wrong to kill or directly cause the killing of animals
It is wrong to have a livelihood on the business of meat
It is wrong to consume meat that is from an animal that is seen, heard or suspected to have been slaughtered specifically for you
It is ok to purchase and consume meat from the market (already dead before you arrived at the market)

My thought is that although the last case is not wrong due to an individual not being the direct cause of the killing of the specific animal, the individual is still contributing to the general demand that drives the meat market i.e. encouraging the supply of meat by butchers. If there is no demand, then there would be no supply. Unlike a tiger killing its prey, a butcher only slaughters the animal if there would be purchasers who would buy its meat.
So, why is this not considered wrong by Buddhists?
EDIT: Preferably, according to the Theravada tradition.

user6921: I practice mahasi sayadaw -  and from my personal understanding its best not to eat meat cause its wholesome  - its hard for me to explain all the ways it is wholesome but i think it helps in compassion and in self control like another extra precepts that can help  the practice even though its not a must 
i also found this text but not of theravada which talks about meat eating :  
Many of the Bodhisattva precepts are about not harming, either oneself or others, or animals.  The first major precept is to ‘Refrain from taking life’.  It points out in great details that one should not kill oneself, nor cause someone else to do it, nor do it in a roundabout way, nor create the cause or conditions, nor the means to kill.  It is an exhaustive list that makes us reflect on the many ways by which we might cause harm.  We might not kill other people or any living creatures but do we cause them harm in any other way.  And if we cause them harm, how do we do it?  Do we do it in a round about way so we do not feel responsible for it?   Do we create the causes and conditions for causing harm needlessly?  These precepts show us that wisdom and compassion help us to reflect on our actions and intentions.  Then the precept explains why we should not kill and that is because the duty of a Bodhisattva is to be always compassionate and to lead others to liberation.
There are several precepts that investigate what it means to be non-harming due to a compassionate attitude.  The third major precepts, which encourages proper sexual behaviour, states that the reason for doing so is that otherwise perverted, indecent, indiscriminate sexual behaviour would cause compassion to disappear.  When one is in the power of lustful thoughts or feelings, can one reflect on what would be the compassionate things to do for all involved in that moment?  This precept  reminds us: “It is the duty of a bodhisattva to always present a state of mind which conforms to the Buddha-nature and to lead others to liberation by teaching them the pure Dharma.”   
The third secondary precept encourages vegetarianism on the ground that if someone were to eat the flesh of animals he would destroy great compassion and great kindness and the seed of the Buddha-nature.  To this day monasteries and nunneries in China and Korean are completely vegetarian.  Since it seemed more difficult for laypeople to be fully vegetarian then six specified fasting or vegetarian days a month were created as well as three special months of abstinence, i.e. times when one avoids animal food. 
taken from : 
https://www.stephenbatchelor.org/index.php/en/compassion-in-action

user295: The key here is volition > fabrications.
In Buddhism this one one of the main points to be focused on. Though demand means that animals will get killed to supply the demand, for the person consuming there is not volition to kill. If any body wants to take a step further and become vegetarian / vegan then it is up to the individual.
Here volition to feast should not be mistaken with volition to kill. If you have to complete the karma of killing:

it should be directed at the animal rooted in either aversion (e.g. pests), carving (e.g. to have a good dinner), ignorance (e.g. ritual)
you should know this is alive
you should have a method to kill it
you should follow through with the method
as a result the animal should get killed

In the case of chicken dinner:

we crave for taste
we device a plan too shopping and then cook or go to a restaurant or something else


this can involve butchering the animal or hunting in which case this is equivalent to killing

we follow through with it
as a result our craving is momentarily stratified

Through both creates fabrication much of the it is differently motivated. One has the animal as the subject the other has mere eating as the subject. If you are thinking to eat a particular animal then it will be volition to kill.

If you look at this more deeply. Also only two things Buddha taught is unsatisfactory nature of existance and how to come out of it. Buddhism basis of morality is no exception and is very objective in what it is supposed to achieve. That is to train yourself come out of misery. Buddhist morality is not a right or ritual, a vow, philosophy, custom, fashion, personal value system, belief or ideal you adhere to, etc. (At some point you will understand morality predicated on this basis will not take you to the final Buddhist goal. But until some time you have to do it as a personal value system or principle.) This is a tool or a step in the process which you train yourself to come out of misery and means to create the best contritions for concentration and wisdom.
You need to dissolve all your fabrications. Any through which is contrary to morals will manifest as an unpleasant sensation. Unpleasant sensation means new negative fabrication are created. The goal of the Buddhist teaching it to identify the psychological root of suffering and eliminate it. Any volition which results in solidifies / gross sensation should be let go of. (Initially a person practising will  practice morality as a vow, custom, personal belief, etc. but later will become automatic when one sees the fabrication process.) The moral basis of Buddhism is that you do not create any fabrication.
If you hold on to a view that eating meat is bad this contributes to your misery as it adds to your base of perceptions or conditioned responses of the mind. Thoughts proliferating will create sensation and reaction will further create fabrications. The view on the matter will feed in to ignorance as you have an expectation and yard stick against which you evaluate the events in the world. E.g. your mental reaction if you see a monk eating meat. This is just contributing to the notion of control and identity. Control - you have a clinging that thinks are ordered in a certain way but it is not ordered in the way you wish. Identity - you are holding into a view and a yardstick as your view or take on the matter. Also morality as a vow, ritual, ritual, or belief - basis on morality is ignorance but not the process of identifying the creating of fabrication.
Basis of basis of Buddhist morality is volition and fabrication and the way to stop fabrication a means to get out of misery, than philosophical ideal to which every one should adhere to. Also morality is a tool in the process that the end itself. At a more micro level is thought > mind sense door > contact > register > evaluate > sensation > craving > clinging. You have to make sure any ideas are ones which do not give unpleasant sensations. Cultivate things will give you blissful or neutral / comfortable / relaxing sensations. Craving for food does have it downside but sensation mark different when you are motivated to kill. Also holding into a dietary / lifestyle ideal may have more decremental than a food craving at the level of fabrication as well as perception and view accumulation. To get out of misery you have to get out of the process of fabrication.

user151: Eating meat is bad karma. So what if it's an intellectual or conceptual argument? When buying meat, you don't have volition to kill but you have volition to eat the flesh of an animal killed for you the end consumer. A monk would be breaking the monastic code if they were out there shopping for pork chops. Are the first five precepts not  conceptual, as well? 
Conceptual reality is a reality too :)

user111: The issue with this question is that it assumes that vegetarian food production does not kill animals. Farming causes many deaths due to deforestation, pesticides, weedicides, electric fences and other animal traps. It can also contribute to landslides which even cause human deaths. So when you buy meat from the supermarket, if you are responsible for the animal who was slaughtered, you are also responsible for the animals killed in vegetarian food production, when you buy vegetarian food. 

user254: Reading the article, the first half of it is directed to monks:

Monks accept charity
Monks don't pay for food (so they don't "contribute to the market")
Monks shouldn't refuse meat (if lay people choose/prefer to give them meat) because that (monks expressing a dietary preference and refusing) would make the monks more difficult to support


As for the message to lay people (not monks), the article seems to summarize as:

Being vegetarian isn't sufficient to liberate people from suffering (so instead of teaching vegetarianism, the Buddha teaches the 4 noble truths, the 8-fold path, etc.)
Being vegetarian isn't sufficient to prevent people from participating in indirect killing (e.g. clearing land for housing, for vegetarian crops, for driving, results in animals' being dying or killed)
Being vegetarian isn't sufficient to prevent animals from dying (animals would die and/or kill each other even if all humans were vegetarian)


I personally agree with the article's "commentary" more than with the article itself.
As a lay person who has some choice about how to spend "my" money, I find the "market demand" argument persuasive. My personal preference is to be vegetarian but not to criticize the choices that others make.
I also know some people (non-Buddhists) who raise, slaughter, and eat their own animals: and I don't see these people as less ethical than those who buy meat ready-killed and butchered from a supermarket.
The Dhammapada says,

All tremble at violence; all fear death. Putting oneself in the place of another, one should not kill nor cause another to kill.

The Buddha is quoted in the article as saying,

I say that there are three instances in which meat should not be eaten: when it is seen, heard, or suspected (that the living being has been specifically slaughtered for oneself)

I choose to interpret "paying a butcher" as being the same as, "causing another to kill", as well as, "the living being has been specifically slaughtered for oneself"; but I understand that this is a 'non-canonical', view which not every Buddhist will or must agree with.
In summary, if you want to think or if you actually think that it (eating and/or buying meat) is wrong, and if you want to choose to be vegetarian, then I think there's some scripture which allows you to do that ... but there's not enough in the scripture to let you 'split the Sangha' and to argue that other Buddhists (who aren't vegetarian) are wrong.
why is this not considered wrong by Buddhists?
I think that Buddhists consider a lot of things wrong: and that "this is considered wrong" is an example of the first noble truth! What good is there in criticizing what other people choose to do?
In Buddhism, the views on vegetarianism vary between different schools of thought.
The commentary to the article you posted is written by a venerable who "was first ordained in the
Chinese Mahayana tradition. In 1986 he was re-ordained in
the Therāvada tradition in Thailand."

user2469: Because buddhist morality is not about regulations and punishments for bad deeds. It's about the effect actions have on your well being, and others' well being. It's "medicinal morality", rather than "legalist morality". And what is bad for the mind's health is to act with malicious intentions. 
This perspective on morality is completely different from our western morality which is still influenced by a christian view of exterior punishment for bad deeds. The punishment comes from you alone and is thus rooted in your intentions behind the deeds.
In this case, this is just one more instance of how suffering in the world is innevitable. It's not that being vegetarian is irrelevant. It is obviously a wholesome thing to do. But there are far more important things to worry about regarding what is good and what is bad for the mind, because when you buy meat you don't have the intention to kill animals. Just like when you walk the street you have no intention to kill bugs, even though that is completely innevitable in the long run.

471: <p>According to <a href="http://thedailyenlightenment.com/2010/07/the-buddha%E2%80%99s-real-views-on-meat-eating/" rel="noreferrer">this article</a> by Ven. Dhammavuddho Thero:</p>

<blockquote>
  <p>Majjhima Nikaya 55 ..... The Buddha denied this, adding “Jivaka, I
  say that there are three instances in which meat should not be eaten:
  when it is seen, heard, or suspected (that the living being has been
  specifically slaughtered for oneself) … I say that there are three
  instances in which meat may be eaten: when it is not seen, heard, or
  suspected (that the living being has been specifically slaughtered for
  oneself).”</p>
</blockquote>

<p>And another quote from the same source:</p>

<blockquote>
  <p>Anguttara Nikaya 8.12 ..... This is one of the discourses which clearly
  shows that the Buddha and his monks ate meat. Also, we see that meat
  from an animal that is already dead when it is purchased is allowed to
  be used, but not if the animal is alive.</p>
</blockquote>

<p>In summary from the above and various sources:</p>

<ul>
<li>It is wrong to kill or directly cause the killing of animals</li>
<li>It is wrong to have a livelihood on the business of meat</li>
<li>It is wrong to consume meat that is from an animal that is seen, heard or suspected to have been slaughtered specifically for you</li>
<li>It is ok to purchase and consume meat from the market (already dead before you arrived at the market)</li>
</ul>

<p>My thought is that although the last case is not wrong due to an individual not being the direct cause of the killing of the specific animal, the individual is still contributing to the general demand that drives the meat market i.e. encouraging the supply of meat by butchers. If there is no demand, then there would be no supply. Unlike a tiger killing its prey, a butcher only slaughters the animal if there would be purchasers who would buy its meat.</p>

<p>So, why is this not considered wrong by Buddhists?</p>

<p>EDIT: Preferably, according to the Theravada tradition.</p>
 6921: <p>I practice mahasi sayadaw -  and from my personal understanding its best not to eat meat cause its wholesome  - its hard for me to explain all the ways it is wholesome but i think it helps in compassion and in self control like another extra precepts that can help  the practice even though its not a must </p>

<p>i also found this text but not of theravada which talks about meat eating :  </p>

<p>Many of the Bodhisattva precepts are about not harming, either oneself or others, or animals.  The first major precept is to ‘Refrain from taking life’.  It points out in great details that one should not kill oneself, nor cause someone else to do it, nor do it in a roundabout way, nor create the cause or conditions, nor the means to kill.  It is an exhaustive list that makes us reflect on the many ways by which we might cause harm.  We might not kill other people or any living creatures but do we cause them harm in any other way.  And if we cause them harm, how do we do it?  Do we do it in a round about way so we do not feel responsible for it?   Do we create the causes and conditions for causing harm needlessly?  These precepts show us that wisdom and compassion help us to reflect on our actions and intentions.  Then the precept explains why we should not kill and that is because the duty of a Bodhisattva is to be always compassionate and to lead others to liberation.</p>

<p>There are several precepts that investigate what it means to be non-harming due to a compassionate attitude.  The third major precepts, which encourages proper sexual behaviour, states that the reason for doing so is that otherwise perverted, indecent, indiscriminate sexual behaviour would cause compassion to disappear.  When one is in the power of lustful thoughts or feelings, can one reflect on what would be the compassionate things to do for all involved in that moment?  This precept  reminds us: “It is the duty of a bodhisattva to always present a state of mind which conforms to the Buddha-nature and to lead others to liberation by teaching them the pure Dharma.”   </p>

<p>The third secondary precept encourages vegetarianism on the ground that if someone were to eat the flesh of animals he would destroy great compassion and great kindness and the seed of the Buddha-nature.  To this day monasteries and nunneries in China and Korean are completely vegetarian.  Since it seemed more difficult for laypeople to be fully vegetarian then six specified fasting or vegetarian days a month were created as well as three special months of abstinence, i.e. times when one avoids animal food. </p>

<p>taken from : </p>

<p><a href="https://www.stephenbatchelor.org/index.php/en/compassion-in-action" rel="nofollow noreferrer">https://www.stephenbatchelor.org/index.php/en/compassion-in-action</a></p>
 295: <p>The key here is <code>volition &gt; fabrications</code>.</p>

<p>In Buddhism this one one of the main points to be focused on. Though demand means that animals will get killed to supply the demand, for the person consuming there is not volition to kill. If any body wants to take a step further and become vegetarian / vegan then it is up to the individual.</p>

<p>Here volition to feast should not be mistaken with volition to kill. If you have to complete the karma of killing:</p>

<ul>
<li>it should be directed at the animal rooted in either aversion (e.g. pests), carving (e.g. to have a good dinner), ignorance (e.g. ritual)</li>
<li>you should know this is alive</li>
<li>you should have a method to kill it</li>
<li>you should follow through with the method</li>
<li>as a result the animal should get killed</li>
</ul>

<p>In the case of chicken dinner:</p>

<ul>
<li>we crave for taste</li>
<li>we device a plan too shopping and then cook or go to a restaurant or something else

<ul>
<li>this can involve butchering the animal or hunting in which case this is equivalent to killing</li>
</ul></li>
<li>we follow through with it</li>
<li>as a result our craving is momentarily stratified</li>
</ul>

<p>Through both creates fabrication much of the it is differently motivated. One has the animal as the subject the other has mere eating as the subject. If you are thinking to eat a particular animal then it will be volition to kill.</p>

<hr>

<p>If you look at this more deeply. Also only two things Buddha taught is unsatisfactory nature of existance and how to come out of it. Buddhism basis of morality is no exception and is very objective in what it is supposed to achieve. That is to train yourself come out of misery. Buddhist morality is not a right or ritual, a vow, philosophy, custom, fashion, personal value system, belief or ideal you adhere to, etc. (At some point you will understand morality predicated on this basis will not take you to the final Buddhist goal. But until some time you have to do it as a personal value system or principle.) This is a tool or a step in the process which you train yourself to come out of misery and means to create the best contritions for concentration and wisdom.</p>

<p>You need to dissolve all your fabrications. Any through which is contrary to morals will manifest as an unpleasant sensation. Unpleasant sensation means new negative fabrication are created. The goal of the Buddhist teaching it to identify the psychological root of suffering and eliminate it. Any volition which results in solidifies / gross sensation should be let go of. (Initially a person practising will  practice morality as a vow, custom, personal belief, etc. but later will become automatic when one sees the fabrication process.) The moral basis of Buddhism is that you do not create any fabrication.</p>

<p>If you hold on to a view that eating meat is bad this contributes to your misery as it adds to your base of perceptions or conditioned responses of the mind. Thoughts proliferating will create sensation and reaction will further create fabrications. The view on the matter will feed in to ignorance as you have an expectation and yard stick against which you evaluate the events in the world. E.g. your mental reaction if you see a monk eating meat. This is just contributing to the notion of control and identity. Control - you have a clinging that thinks are ordered in a certain way but it is not ordered in the way you wish. Identity - you are holding into a view and a yardstick as your view or take on the matter. Also morality as a vow, ritual, ritual, or belief - basis on morality is ignorance but not the process of identifying the creating of fabrication.</p>

<p>Basis of basis of Buddhist morality is volition and fabrication and the way to stop fabrication a means to get out of misery, than philosophical ideal to which every one should adhere to. Also <strong>morality is a tool in the process</strong> that the end itself. At a more micro level is <code>thought &gt; mind sense door &gt; contact &gt; register &gt; evaluate &gt; sensation &gt; craving &gt; clinging</code>. You have to make sure any ideas are ones which do not give unpleasant sensations. Cultivate things will give you blissful or neutral / comfortable / relaxing sensations. Craving for food does have it downside but sensation mark different when you are motivated to kill. Also holding into a dietary / lifestyle ideal may have more decremental than a food craving at the level of fabrication as well as perception and view accumulation. To get out of misery you have to get out of the process of fabrication.</p>
 151: <p>Eating meat is bad karma. So what if it's an intellectual or conceptual argument? When buying meat, you don't have <strong>volition to kill</strong> but you have <strong>volition to eat the flesh of an animal killed for you the end consumer</strong>. A monk would be breaking the monastic code if they were out there shopping for pork chops. Are the first five precepts not  conceptual, as well? </p>

<p>Conceptual reality is a reality too :)</p>
 111: <p>The issue with this question is that it assumes that vegetarian food production does not kill animals. <a href="http://theconversation.com/ordering-the-vegetarian-meal-theres-more-animal-blood-on-your-hands-4659">Farming causes many deaths</a> due to deforestation, pesticides, weedicides, electric fences and other animal traps. It can also contribute to landslides which even cause human deaths. So when you buy meat from the supermarket, if you are responsible for the animal who was slaughtered, you are also responsible for the animals killed in vegetarian food production, when you buy vegetarian food. </p>
 254: <p>Reading the article, the first half of it is directed to monks:</p>

<ul>
<li>Monks accept charity</li>
<li>Monks don't pay for food (so they don't "contribute to the market")</li>
<li>Monks shouldn't refuse meat (if lay people choose/prefer to give them meat) because that (monks expressing a dietary preference and refusing) would make the monks more difficult to support</li>
</ul>

<hr>

<p>As for the message to lay people (not monks), the article seems to summarize as:</p>

<ul>
<li>Being vegetarian isn't sufficient to liberate people from suffering (so instead of teaching vegetarianism, the Buddha teaches the 4 noble truths, the 8-fold path, etc.)</li>
<li>Being vegetarian isn't sufficient to prevent people from participating in indirect killing (e.g. clearing land for housing, for vegetarian crops, for driving, results in animals' being dying or killed)</li>
<li>Being vegetarian isn't sufficient to prevent animals from dying (animals would die and/or kill each other even if all humans were vegetarian)</li>
</ul>

<hr>

<p>I personally agree with the article's "commentary" more than with the article itself.
As a lay person who has some choice about how to spend "my" money, I find the "market demand" argument persuasive. My personal preference is to be vegetarian but not to criticize the choices that others make.</p>

<p>I also know some people (non-Buddhists) who raise, slaughter, and eat their own animals: and I don't see these people as less ethical than those who buy meat ready-killed and butchered from a supermarket.</p>

<p>The Dhammapada says,</p>

<blockquote>
  <p>All tremble at violence; all fear death. Putting oneself in the place of another, one should not kill nor cause another to kill.</p>
</blockquote>

<p>The Buddha is quoted in the article as saying,</p>

<blockquote>
  <p>I say that there are three instances in which meat should not be eaten: when it is seen, heard, or suspected (that the living being has been specifically slaughtered for oneself)</p>
</blockquote>

<p>I choose to interpret "paying a butcher" as being the same as, "causing another to kill", as well as, "the living being has been specifically slaughtered for oneself"; but I understand that this is a 'non-canonical', view which not every Buddhist will or must agree with.</p>

<p>In summary, if you want to think or if you actually think that it (eating and/or buying meat) is wrong, and if you want to choose to be vegetarian, then I think there's some scripture which allows you to do that ... but there's not enough in the scripture to let you 'split the Sangha' and to argue that other Buddhists (who aren't vegetarian) are wrong.</p>

<p><em>why is this not considered wrong by Buddhists?</em></p>

<p>I think that Buddhists consider a lot of things wrong: and that "this is considered wrong" is an example of the first noble truth! What good is there in criticizing what other people choose to do?</p>

<p><a href="http://en.wikipedia.org/wiki/Buddhist_vegetarianism" rel="noreferrer">In Buddhism, the views on vegetarianism vary between different schools of thought.</a></p>

<p>The commentary to the article you posted is written by a venerable who "was first ordained in the
Chinese Mahayana tradition. In 1986 he was re-ordained in
the Therāvada tradition in Thailand."</p>
 2469: <p>Because buddhist morality is not about regulations and punishments for bad deeds. It's about the effect actions have on your well being, and others' well being. It's "medicinal morality", rather than "legalist morality". And what is bad for the mind's health is to act with malicious intentions. </p>

<p>This perspective on morality is completely different from our western morality which is still influenced by a christian view of exterior punishment for bad deeds. The punishment comes from you alone and is thus rooted in your intentions behind the deeds.</p>

<p>In this case, this is just one more instance of how suffering in the world is innevitable. It's not that being vegetarian is irrelevant. It is obviously a wholesome thing to do. But there are far more important things to worry about regarding what is good and what is bad for the mind, because when you buy meat you don't have the intention to kill animals. Just like when you walk the street you have no intention to kill bugs, even though that is completely innevitable in the long run.</p>
