To be honest, I didn't think about it too much, I just thought it'd be interesting to play a map that's just one big town and nothing else. You'd have to go about it very differently, I think. No mining would mean not a whole lot of gas, for instance, so you'd have to pick and chose where to go by motorcycle and where to walk or ride your bike. There'd also be very few trees, so finding a large amount of wood would be like a christmas present. You'd also have to be more careful with your ammunition since you just can't grind some resources to get some. Things like that. It'd be an interesting way to play, I believe.
Performance issues would be a thing, of course, but maybe it'd be not that bad, I don't know. I know I can't run towns for s**t because my computer is ancient, but maybe it's not that bad for many other players. And for me, once I get myself basically an entirely new computer.