It's not just "cities".
I know of entire communities far from urban centers that would not exist as they do today without welfare or other wealth transfer programs. These communities have little business or industry beyond retail; meaning that they produce and export next to nothing; they exist solely by the money brought in via transfer payments. Recipients flock to these communities because the cost of living is a fraction of what it is in the city, and one can live a reasonable middle class existence without working.