In TS2 this was never an issue because no matter how big the hood was, only the active lot was what mattered. It would require for me to add much more sims into the world to have a big city buzz feel in such a big hood but if I would do that, I'd end up with a laggy game because I have too many sims that the game tries to handle at once. I have added some families there but it's not enough for such a big hood. When I play bigger hoods like Jericho, the bars are empty. Like when Emsley and his family went to Red Desert, they spent most of their time in the pool and it was popular enough that Emsley (who's in the pool) was able to find himself a new girlfriend even though Carmen (who's walking behind him next to lady gaga), found herself single after the plain brought them back to the main hood. But still, they don't have to spend their days alone on empty lots. When my sims travel to other towns, they do have to get used to less people around them because the travel destinations are bigger than my town. The only time I have empty town syndrome, is when I'm playing bigger hoods, where there are too many places for the sims to go, and too few sims to occupy these locations.

If the spot is a hot-spot, it gets filled with sims. Even the ones that are not the hot-spots, have at least 1-2 sims in them when my sims visit.

My town is very small, I have only three places the game thinks can be a hangout, the bar, the nectary, a café. The amount of people in community lot has to do without your system/your town's size/population size.

Sims 3 large empty world red