Glitter Jelly:
I've often wondered about that, since this theme is so prevalent in the stories section...
If I had to guess, there might be 2 things going on:
1) That kind of revenge-by-getting-fat trope is common in a lot of media, it's been around forever, and I'm sure there are quite a few people in this community today who discovered they liked weight gain (or erotic weight gain media) because of tropes like that in "straight" media -- they just liked it for a different reason than how the author intended, maybe. Maybe not.
2) A lot of the stories on this site are taking well worn tropes like this one and putting the author's own take on it, and the author might not be thinking that hard about the origin of the trope they're mimicking, because it's something they always thought was hot. They might not have seen it the way it was intended to be seen, kinda subverting a problematic trope, but maybe inexpertly making that clear. Or not. It's amateur art, though, people trying things out.
