There are many ways of looking at the US, but quality of life is more than just cost of living. The same house might cost 50k or 2.5 million just based on location, but you can't buy pollution free air, low traffic levels etc. On the other hand there are many advantages to living in or near a mega city like a wide range of good restaurants.
Even things as basic as crime stats get mixed into this. People simply get away with less crap in city's.
Getting back to politics I think America is simply less unified than people assume. People live vastly different lives and want a wide range of things.