Give me a break. I lived in San Francisco for a bunch of years, starting after my first company got bought out --- I've experienced the city both totally flush with cash and living paycheck to paycheck. Allow me to retort:
* Public transportation in the Bay Area is a shambles, and, in particular, getting between any two points in the (tiny) city of San Francisco involves interaction with the worst bus system in the country.
* Housing is spectacularly expensive, which, in hacker teams, simply means you're going to be living in half the space you have now, with no amenities.
* Office space in San Franscisco? I already spent the modifier "spectacular", so let's go with "catastrophically" expensive, meaning: your office won't be in the city, it will be in San Mateo, which despite its relative proximity to the city, will still be an hour and a half commute. Unlucky enough to wind up in Santa Clara? I was. My commute from SOMA often exceeded two hours each way.
* Half to 3/4s of your friends are going to live in the South Bay. No matter where you choose to live --- San Francisco or the suburban Mallhalla of the South Bay --- you are going to be 45 minutes to an hour away from anyone you want to visit.
* An ongoing dispute between the dispatchers, the city, and medallion owners keeps taxicabs artificially scarce, so that you are going to wait 20 minutes to catch one on Folsom or downtown.
* There isn't one good place in the city to see a show, but that doesn't matter, because your favorite band skips San Francisco.
* Last call in San Francisco? Earlier than other cities.
* Weather? Choose between "brown" or "wet".
* Streets? Laden with human feces and garbage. Am I being hyperbolic? No.
Almost any other city in the country, save Los Angeles, can lay a better claim to being a destination for long-term lifestyle companies than San Francisco.