I moderated plenty busy forums that had rules and ToS, but I didn't think of violations as anything more than something that might lead to me terminating an account.

Now one greifer did have a habit of mass producing accounts quite cleverly and the parent company actually sued him in civil court, but that was unique and actually disrupted the entire site with griefing and such. They even got the ear of a local prosecutor who thought that disrupting the site might count as a criminal act. The griefer went away after that and nothing came of it other than filing a civil case and I belive some contact with the local prosecutor... dude agreed to go away forever.

But of course in the example they are talking about just creating a fake account and speaking more generally about ToS violations.