Q:

Any difference between "Good morning, Brian" and "Good morning to you, Brian"

I often hear it on TV when they are talking to a guest.
Normally, if we want to greet Brian in morning, we would say "Good Morning Brian". But many times TV presenters say "Good morning to you Brian".
Why is that? Why do they add "to you". There seems to be no need to do it.
Regards,

A:

You’re right, it’s not needed – but it still adds a personal touch. 
Your question reminds me of this exchange, found early in Tolkien’s book The Hobbit: 

“Good Morning!" said Bilbo, and he meant it. The sun was shining, and the grass was very green. But Gandalf looked at him from under long bushy eyebrows that stuck out further than the brim of his shady hat.
"What do you mean?" he said. "Do you wish me a good morning, or mean that it is a good morning whether I want it or not; or that you feel good this morning; or that it is a morning to be good on?"
"All of them at once," said Bilbo.

A:

The "to you" is generally used only where there is an audience (i.e. third parties listening or watching), especially if:
(a) there are several people to whom the "good morning" could be addressed, and/or
(b) if the audience cannot see the person to whom the remark is being addressed (e.g. a radio programme or a podcast).  
The key point is that the greeting is directed at a particular person.
For instance, on TV or in a podcast, the phrases "Good morning to you Brian, and also to you Yunus", or  "Thanks Brian, great answer, now over to you Yunus for your reply" are examples of when the "to you" would be appropriate.
The phrase might also be used in other group settings - e.g. in a classroom, where the teacher might say: "Good morning to you, Sally, could you please tell the class ...".
Note that on TV or radio, the "to you" does tend to add a bit of a casual and familiar tone; it would rarely be used during very formal communications.  For instance, starting an interview with "Good morning to you Prime Minister" is less formal than "Good morning Prime Minister" and would be appropriate only if a familiar tone is acceptable in the circumstance.  You can see this by listening to discussions in serious forums (e.g. in a court room, in the United Nations, etc) where the "to you" would be extremely rare.

