This is all true, and is definitely a primary factor. It's also true that LA and NY draw people from all over the country. Have you ever been to LA or Manhatta

This is all true, and is definitely a primary factor. It's also true that LA and NY draw people from all over the country. Have you ever been to LA or Manhattan? Nobody that lives there is from there. Those places are alternate-reality bubbles, for sure, but lots (most?) of those people were born somewhere else and likely grew up in a more representative part of the country. So, I think there's also an element of "artist" types rebelling against what they felt were stifling suburban upbringings? Totally unproveable of course. Just a feeling I've always gotten.