I thought about this one for a while and I can't think of anyone who collects cute mugs specifically.

the obvious answer is Tweek but I don't think he owns too many mugs, actually. he has maybe three in his possession, they're solid colored and unremarkable and chipped to hell. maybe Nichole? she probably receives nerdy ones often as gifts, like DnD-themed and the like, but not enough to build a collection.

hm, well, I guess in a similar vein to mugs which often strike me as a souvenir type thing, I think Stan collects patches from national parks and new places he visits. I'm not sure if I want them sewn on to a backpack or jacket or if I think he puts them in a framed display but- nonetheless he collects them. he does not like getting them as gifts though. it has to be a place he's actually been to himself.