Or you can move if you can't afford the area. There are plenty of places with lower costs of living. You can't live in what is perhaps the most desirable area in the world and then be upset that people want to protect/increase their property value or not change how their community is. Not everybody wants to live in a sea of imposing skyscrapers.

-edit

So I see a few comments discussing things like commuting, urban sprawl, etc.... Those are fair comments and I largely agree. But the solution proposed is not the right answer either. We need mixed-use developed walkable neighborhoods. We need our work places to be mixed within our neighborhoods along with our parks, convenience stores, and everything in between. Obviously I'm not a fan of sprawl, but I'm not a big fan of skyscrapers, and I'm also not a fan of others being upset about the affordability of the world's most desirable areas. While it is true that there is much more economic opportunity in a place like San Francisco than, say, middle-of-nowhere Arizona or something, it would be incorrect to suggest that there is no economic opportunity. Frankly, the assessment being made here is that you're choosing to suffer a 2-hour each-way commute and unaffordable rent for the opportunity to work at really cool companies, but the solution, which is to force other people to change their way of life, even if you find it contemptable, is an inherently immoral stance. If a town votes in a mayor who does what the town wants, what is more American, and democratic than that? Is overrunning the town with lawsuits and fights an ethical thing to do? I don't think so. Pack your stuff, and move. When (insert company here) can't get employees to relocate to the insanity that is the Bay Area, they'll move their offices, and things will resolve naturally and peacefully.

Disclaimer: I have never lived long-term in the Bay Area and I have no vested interest in how any of this turns out. If anything, reading the horror stories about people subletting camping spots in their backyard and the like amuses me (obviously I feel bad too). I do confess I have a vested interest in promoting mixed-use development neighborhoods and I would like to see more people move out of the Bay Area and back into the rest of the United States as I believe that the concentration of wealth and knowledge in one (or a few) areas is contributing to the fractures in our society and anti-competitiveness of our second and third-tier cities.