It's even worse than that. They preemptively ban you outright on lots of major subs for posting on other subs. For instance, I can't interact with r/pics because I once commented on r/redditachievements. And a housemate once upvoted a pic on there which got us both banned for a week because Reddit thought I was trying to do a run-around on the ban.

I still love Reddit for all its flaws though.