Respectfully, I disagree. If you are running a bar and a nazi comes in with all their nazi periphranalia and orders a drink and behaves. You still kick them out. Because if you don't the next time they will bring all their nazi friends and it will be much harder to kick them out and then your other patrons stop showing up because of all the nazis around and now you are running a nazi bar.
Ban hate trolls. Ban them immediately. Because if that content festers on the site it will be much harder to ban later.