I have tons of hentai manga/doujin and I don't consider it "fappable." Most of it's collected for its novelty or artistic value. There's lots of absolute junk that I don't bother with, but come on, frog on girl action? You can't not have that. This is all going to be very hard to explain if I die suddenly and my family find most of a hard drive full of stuff like that. I don't know why I do it...

As for porn that I "use", it's mostly free video sites and usually pretty bland and standard issue.

It's a kind of hoarding instinct, I think. I don't need it and rarely go through it. It's healthier and cheaper than collecting toys or something. At the very least, it takes up less space!