The culture is just too different and I just don't mean the business culture. It's reflected in all walks of life.
For example, let's take dating. In NYC if you're not making money or on the very fast track to doing so then you might as well not exist. In my experience dating in the Bay Area women are much more accepting of guys who are working on something long term that may or may not payoff (not saying this is always the case, just moreso than other cities I've lived in).
In short, in the Bay Area you get points for being a creative doer, in NYC you get points for already having money in your bank account. The Bay Area culture is just more conducive and accepting of the trials and tribulations of startup life.