It's expensive to uproot which is why the working poor are often trapped in high cost of living areas. OTOH the midwest has had a huge problem for years of 'brain drain,' and that's because there are just fewer highly compensated jobs than what you'd expect in the midwest, and among these salaries are appreciably lower. People don't receive degrees at midwestern schools then move to NYC, SF, LA, wherever else without a job offer lined up, and if they take that offer its because its better than what midwestern companies who are even more active in recruiting of midwestern grads were offering them.