I think sburb would just absorb the whole building the game is running in, and everyone in the building/general area would be sucked into the game too, confused as hell. I imagine the random people inside would have to fend for themselves like Dad Egbert had to (like getting hassled and kidnapped by imps or something?) while you did your gaming. Good for them for being saved from apocalypse! Another thing this made me think of is if you had no home and just ran sburb outside... I think it could take the area around you and you had to work with whatever was in your vicinity.