I've been pretty forgiving to any and all neighbor towns, and have only dumped neighbors who hadn't been active in over a month... but I've found myself leaning more towards the OP view with some of the mass jumble setups of some people in my list (i.e - no roads, no paths, no separation between buildings... just a massive dump with no rhyme or reason). If that's how some want to play the game, more power to 'em.... and during 'normal' times, it's quite easy to find 3 buildings to tap... but during events where you have to find specific things (gamblers, nightmares, etc) it's beyond annoying to find anything....
while I tend to dump new buildings along the edge (especially during events), they typically find their way into the town layout within a week or two... so I understand that kind of disarray (as well as the nuke/redesign chaos, if that's in process), and can forgive/be patient with that.... but for the 'dump' layouts, it's just not fun to visit (to me), so a purge might be in the cards for my neighbor list.