Some of those collections certainly seem OCD- driven (and such is my obsession with basses, particularly white ones).
My Dad was a high school teacher in the 70s-90s and urged his students to bring in empty breakfast cereal boxes. He's got some real rare ones but they're not worth much. But then collecting things that have no intrinsic value to others is sort of an act of rebellion, at least according to author Richard Meltzer, who used to "collect" contemporary soda pop bottle caps by prying them right off while they were still in the old school, horizontal dispensers.
View attachment 2882809
Meltzer discusses at length and with relish these bottle caps, discusses grading, collecting doubles and trading with your friends.
The running joke being that the object of fascination is intrinsically worthless, and thus the collector is suffering
a sort of mania. Thus the whole notion of collecting and appraising is satirized. But of course the ultimate joke is on the author, who, provided he kept his 60's-70' collection of " 'caps ," has no doubt seen the collection appreciate.