You mentioned comments, but you didn't mention people who leave a generic comment and then get it upvoted to the top to advertise their own profile.
I came up with the idea after reading segment #1 of Shark School, don't forget to upvote, share, and resteem your favorite comment squatter @kirkins
What about those assholes that hijack the top comment?
Hang them all!
YEAH!
...no NO WAIT!
hilarious and demonic meme