Running in isolation?

I went running this morning in Marine Park today in Brooklyn. It is a nice park, but the scenery is a bit dull, and the running track is only .84 miles long. So I had to do it 5 times. I noticed that the people in Manhattan who run seem much friendlier than their Brooklyn counterparts. Are the Manhattanites so isolated that they are much more eager to reach out to others in friendship? I think that is the case. In Brooklyn (part of which is America's first suburb) people are not as isolated from all community as they are in Manhattan. The sense of community is much less.