I agree that you need substantially more money for a similar standard of living somewhere like the SF Bay, but the US is very big. Most places are not SF. And let's not forget that there are still poor people in the Bay Area--a lot of them.
We lived in Berkeley for a bit, and it's a great place! Boy, we were broke, though, and not very able to enjoy many of the nice things about it. So we moved somewhere else. (To be fair, we were young, childless, and highly mobile, so this was easy.)
I think a lot of people who are well educated, ambitious, and smart get a little stuck in the mindset of "But I HAVE to live in this pricey, high-status, UMC area (of the country, or of my region) because..." I mean, I get it to some degree, but it's also a little bit fear-based, and sort of a kind of provincialism.
Also, it's only fair to acknowledge that you (general "you"!) are probably living there in part because you really want the advantages that you perceive as coming along with that area. So do a lot of people--so you're paying for them. There are other choices, but you don't want to make them. Which is okay. But they do exist.
