[madcaptenor]

I was thinking along the same lines. I noticed this when I moved from San Francisco to Atlanta -- people in the middle in San Francisco don't have laundry in their apartments, but in Atlanta they do, because in Atlanta people rent larger places than they do in SF. So in Atlanta the laundromat density probably goes down when you move from "low" to "middle", but in SF when you go from "middle" to "high".