I get your point. When you say I don't react and tolarate posts I accept the criticism, but it's not like I do that because I enjoy seeing provocations or because I don't care. I use it as a tactic, which maybe is not the best one everytime, but it's still a tactic.
I find useless to permanently ban in the internet world (if not in case of spam), because I have no way to stop people to come back one day or one year later with another username, another IP etc. Deleting posts and keep an eye on "tricky" users, let's call them like that, allow me and the community to know who is writing it, it gives me the chance to moderate their posts when necessary, it gives users the chance to use the ignore function agiainst them so that their posts will not appear anymore. Banning them will not stop them, on the contrary it might increase their anger and frustration, they will get back to do what they did with another username, and if they are good and people can't recognize who they are, they will give the feeling there are even more people like them.
Again, I'm not saying this is the best way to limit these situations, but I just wanted to explain my point of view. I know it's not easy but the best way, as in real life, is just to ignore them.