I think another aspect of this is that people don't just socialise with people in their immediate neighbourhood anymore too. My friends live all over the city,

I think another aspect of this is that people don't just socialise with people in their immediate neighbourhood anymore too. My friends live all over the city, so why would we go to a local pub to hang out? It's just easier for us to meet in the city centre. In the past (before cars) people used to work and socialise far more locally.