On one antivaccine subreddit years ago, someone who was provaccine posted "Is this a parody sub or are you people serious?", and he instantly got banned from dozens of subreddits, because reddit autoban doesnt care what you posted, only where you post it. Ironically, that made him so angry that he decided to spend more time on that antivaccine subreddit and finally became an antivaxxer himself. XD