Shiny Cars

I have noticed a lot of different things while living in Brentwood/LA. But one of the main things I have noticed is all the BMW's that line the streets and the cars around here are so unbelievably clean. I mean extremely clean. My car looks like it just came out of a junk yard compared to the cars surrounding where I live. Why are the cars so clean here? Is it because I live in a predominantly upper class neighborhood? Or maybe it is because there's no snow here, therefore, cars are less likely to get dirty like in Colorado. Everything is so shiny.