Just seen this interesting thread in Meta and wondered if there is really any good reason not to ban all of these users? If they don't trust an exchange, why should they be paid on that exchange?
You certainly have the right to do so but it would seem kinda retaliatory. Do the campaign rules include anything about disparaging comments regarding Yobit? I don't see that, I see only rules against spamming. So if you want to do it "by the book" I'd say get the rule added and only apply it going forward.