NPC or no NPC?

Does anyone else sort of wish certain "NPCs" would stay NPCs? While it is nice to be able to interact with all Sims without limitations, I find it a bit annoying when what should be a singular character shows up twice or even more because of some strange circumstance or you decided to add the Sim to your Sim family. There should be one Grim Reaper. If any others show up they should be Grimterns. There should be one Night Wraith, rather than a new one popping up each time it visits. There should be one Father Winter and that is Clement Frost. There shouldn't be townies running around as Bonehilda. A strange one to bring up would be the Tragic Clown. It admittedly bothers me that some random townie shows up as the Tragic Clown. It should just be Sonny, the bothersome and somewhat creepy clown that is obviously supernatural in some way. (About the only good thing about the random townie spawning is that you can have multiple unique kills of them, but for a lot of those kills you have to add them to your family. In note of that, why can't we set fire to the clown painting and see [him] suddenly burst into flames?)

Maybe it is just me. I know there are a lot of players who like to marry their Sims to some of these characters or have them added to their families despite some other Sim will spawn and take their place in terms of roles. Still, though... once they become a playable Sim their role is gone and in the end they are basically a normal Sim.