"Socialism never took root in America because the poor see themselves not as an exploited proletariat but as temporarily embarrassed millionaires." - Steinbeck
Very true - but it isn't just Americans, or even mostly Americans (by birth) playing this game, at least in tech.
I've worked with plenty of Indians, Germans, Chinese (fewer hard chargers though - they tend to stay in China more recently), French, Czech, Russians, all here to, for lack of a better phrase - to get paid. More than 'native born' Americans, that's for sure.
Even for 'native born' Americans, they almost all moved to the bay area (or the office/city they are in) from another state, sometimes half way across the country, and almost none grew up in the area the business or office is in. People who are ambitious will move to the opportunity.