Advice on whether to pursue a PhD or not I know this question has been beaten to death over here, but I'm still not sure what to do in my case. I've been given an offer to do a PhD in electrical engineering in a top 10 university and I'm very confused on whether to accept the offer or not. 

Initially I only applied for the MS program and a PhD was not something I wanted. After a few professors interviewed me, they asked me to consider changing my application from MS to MS/PhD and mentioned how much I would be paying if I did MS only since there is absolutely no funding for MS students. I was worried about the cost of going to grad school without funding, so I caved in and changed my application to MS/PhD. 

For starters, I don't know if I am willing to put the time necessary for completing the PhD: I somewhat like the things I would do research on if I accepted the offer (information theory and coding theory), but I wouldn't call myself passionate about the subject or any subject in electrical engineering for that matter. Also, my priority (and possibly the only thing important to me right now) is financial security and being as financially "well-off" as possible, so would doing a PhD really make a difference in that regard if it's from a top university? This is the only case where I would be willing to put in the effort for PhD.   

Please note that I am not asking people to decide for me, I am asking for different perspectives or points of view to make the decision easier for me.
So if you accept a PhD offer in the US, you can normally leave in the middle with a master's. This is better than enrolling in a master's program since you don't have to pay (in fact, you'll get paid a small stipend). I recommend researching your institution's policy on this. 

If this is the case, you can begin your PhD program now and then decide in a few years whether to leave with the master's or finish the PhD. I do not know whether the PhD is a good investment in your long term financial plans, but I'm reasonably certain you will need more than a bachelor's.