The KKK in his name could be an acronym for Ku Klux Klan, it might not be. For the sake of argument, let's assume that it is.
Shouldn't we be politically correct and respect his or her ideological differences? Shouldn't we be tolerant, even if we don't think they are? They shouldn't be banned because someone takes their own interpretation of the name and decides to be appalled by it. After all, ANY name that might represent a philosophy, belief system, or culture can be construed as offensive to someone, somewhere. A whole lot of people would need to be banned. That is, if fairness were of any concern.
Acceptance and political correctness may not work for you. The only other way to be fair would be to ban EVERY person whose name can be perceived to be associated in any way with any group. (Remember: somewhere in the world, someone will be offended by any group). I've seen a MormonAce, a Bpanther, and a Commie3 before. Each of these names, or the groups they may represent, might be deeply offensive to some people. If KKKUNITE is a name that will get you banned, so should the three listed. I should probably be banned as well. My name, WalrusG, represents bear food. All those folks who say, "Don't feed the bears," are most likely stricken with horror upon seeing my name.