To those people who believe this is the fault of tech - I have a question. What is the ethical way to move to San Francisco? Or anywhere in the Bay? What do you think is a good solution to this, beyond some variant on tech people owing undefined amounts of money to everyone else?
My problem is this: a lot of tech companies, based outside San Francisco go out of their way to make it easy for employees to live in SF and get to work outside of it. This is bad for the people who have lived there for a long time as they can't compete with the money the tech industry brings to the market. If your job is in SF I think it's perfectly fine to live there no matter what industry it's in. But taking space and driving up the price of space that could be used by someone who NEEDS to live there (e.g. a local butcher/hairdresser/convenience store owner) when you don't is unethical in my opinion. Not to mention that if those people can't live in the city and close down or move their businesses your life there won't be as good. It's not illegal and like all ethical questions the answer will differ from person to person but that's what I think about it.
Edit:
Of course the problem is the mindset of a lot of tech people (evident in this thread). They think logically and love 'the free market'. They're also predominantly young. They don't understand living in a place for 30/40 years and being forced out. They seem to ignore the emotions involved or feel they are irrelevant.