It depends on the world state. In my Vampire game (which I’m going to be gutting and revamping due to witches now coming) they are pretty widely spread out. Strangerville even has a Vamp- despite being the home of the main SimNation Slayer clan. (She is very quiet, sneaky, and has been there forever so... the few slayers who have tried to off her have not succeeded, and because she is now the hero of Strangerville they pretty much aggressively ignore her existence.)
Then we got my main legacy family world where right now, yeah, most are in Midnight Hollow. That may change with how Dracmorda is recruiting but it would take awhile.