That’s fine if you’re into vanilla porn, but if you have a fetish even slightly more niche than what they’ve got on ex: Kink.com, you’re not going to find more than a handful of videos for free (unless you go with piracy but that’s beside the point). And those will be digitized German VHS tapes. And will be out of focus. So in situations like that, paying for porn (or, paying to support creators that produce content you enjoy) becomes a lot more attractive as an option.