To me, it feels like cities get people who've been backed into a corner by capitalism.
Where their only option to make enough money to survive is a badly paid job in a city where their only option for accommodation is small and not pleasant.
And a lot of the feel of a city is reflected by that.
If you are forced to work 50+ hours a week on unpredictable contracts, and your entire world shrinks to a bedroom, a car choked walk to work, and Tesco Metro, you're less likely to be saying "good morning" to people as you pass them.