[GTA] Why does anyone even live in the cities?

In the GTA series, the various cities that the games are set in are usually rampant with crime. If it isn't the player characters going on a rampage, then it is either the police, or the other citizens that will be easily driven into a homicidal rage for such minor things as being bumped into while walking down the road/minor collisions.

Why would anyone bother to live there? It seems wildly unsafe, even before the various other criminal enterprises get involved.