[waboremo]

Outside of buying accounts, some people literally just want control. For the same reason that people will spend countless hours moderating large subs for free. They want to push certain narratives on subs, so you'll see large accounts where all they post are generic filler distractions or inciteful links. It's not all super nefarious or political, often it's things like mindless fanboy wars, where they only post things that make their favorite companies look good.

For others, they do it because getting upvotes and reddit awards makes them feel good. They see themselves as community pillars. I suppose this kind of feeds into the above reason in some ways.

If you check /r/games today, you'll see one user is responsible for over half of the submissions. Such accounts are what I mean, where unless they have fine tuned a bot to such a degree, they're really just someone with a little bit too much time on their hands.