I live in Seattle, but have worked remotely on a startup based in SF. There is definitely a cultural difference. Many of the SF folks I know seem to be ashamed to work for a big company and not "doing their own thing". These people work for very well respected companies with great products, but always seem to be planning their escape to something new. If you are doing some crazy ridiculous experimental thing in SF, it is "cool".
In Seattle, I have talked to many employees of Amazon and Microsoft and they seem more proud of working at a top big-name company. They are working on products that are already used by millions of people around the world. When I mention that I work on no-name startup, I sometimes get the feeling that they feel bad for me. It's like "Oh that's cute, if you are looking for real job, I can probably get you in at Amazon".