Why are most urban Blacks so ethnocentric?

I live in Bridgeport, CT where the population is a pretty even mix of Blacks and Whites. However, I have to say that in 21 years of living in the city, I have never, not one single time, been next to anyone Black listening to Guns n Roses, or Metallica, or Linkin Park, or any rock/alternative/etc type band. Further, I have been in many of their homes and I always see Jet magazine, Essence, Ebony, XXL, etc. On tv 99.999% of the time is B.E.T which always makes me wonder why bother having other channels. And the few times the channel changes it's either to a basketball game, or one of the channels with Black programming like the CW. There are always things like incense and fake African type products like Leopard print blankets, etc. The food is almost always ethnic like fried chicken, collared greens, curried everything, etc. Their cars always have dark tints, and rims, and a subwoofer, even if it comes from Walmart and rattles the car. Their clothing style is completely different like hoodies, puffy jackets, camouflaged Yankees hats that are never seated right and always turned to the right or left on an angle. Their pants STILL never have a belt and are usually hanging down, a trend I thought was a trend but 20 years later it's still happening. What gives? Why separate themselves from everyone else?