I get paid just a little below their averages and I'm not quite the calibre of a Google/MS/Amazon developer. Plus I'm on the east coast in NC where the CoL is definitely cheaper.
Google/MS/Amazon do have some VERY smart developers. But there are dolts too at the big ones. The fact that you realize there are better developers than you puts you above most. A lot at MS think that because they work at MS they are the best thing in the world for software.