They generally like hiding behind user rights when it comes to tackling really big issues and its happened in the past too. They are incapable of turning off that community because, as you said, it drives so much traffic and creates so much conflict that they can then use to channel stuff as top hits.
I dont think Chelsea will get any joy out of this route honestly and the best they, or any club, can do is to make sure that people who attend games or travel for games dont promote the idea that the club is okay with racism of any sort.