They do in India. The United States is less stratified but it happens here. I have yet to see a fundie or Pentecostal Church (or KH) in an upper middle class to wealthy neighborhood. I am temporarily living on the outskirts of a major ghetto city. As I speed through the urban blight, I don't see a single mainstream church. All I see are small storefront churches. There is a link to socioeconomic status and choice of church. I see it as a good thing b/c people can choose where they are most comfortable.
I've posted before about watching an episode of Tim Russert's Meet the Press. He had on political consultants who market the candidates. One did it for the Dems, the other one did for the GOP. They explained how how we vote has nothing to do with ideology but was a lifestyle choice. I did not believe them. They listed about twenty consumer items that are scanned when you purchase them. Lettuce, colas, shampoo, antipersperants, etc. Russert indicated his preference before they revealed how it signalled party allegiance. I thought I was quite the sophisticated with a Poli Sci degree. I was horrified. Every single example indicated I was a Dem. Shampoo? Yes. I am certain the same thing happens with religion.
The consumer choices are tabulated from various sources. In the past, if you were the odd Dem in a GOP stronghold, you could not be reached. It would be too expensive. Now they can tell from your grocery items and come knocking at your door.
There has been a massive fracture in American politics since the US was formed. NY vs. the South. Alexander Hamilton, strong central government,, pro business vs. Thomas Jefferson, strong state government until he was President, with profound distrust of cities. Unless you had someone such as George Washington with national experience, the regions differed on the role of government. There were also regional religions. I believe this happens in most countries.