Banned, no logical reason as to why either

Made an account, it's sole purpose was to play a prank on a guildmate and would've ceased to exist after the prank had happened later today. Only reason I see that this account would possibly be banned is a similar name on the Horde side, but that is not grounds for a perma-ban since I am not impersonating them. You can even check the chatlogs and see that I clearly stated to people who messaged me that I was not who they think I was.
Character Mìlky
PvE server, Alliance side
Thank you for your iron fist of justice. Though in this case, it may have been entirely too extreme. I don't care about the account being reinstated, I'll just make another one(unless you can provide a legitimate reason to why I can't create one?). I just want to avoid something like this happening to other users.
One other thing I can't quite understand.. If whatever I did in three or four world chat messages was so terrible to have deserved a perma-ban. Why hasn't someone like Bubblegirl, who is constantly polluting world chat for hours on end not banned yet?
Character Mìlky
PvE server, Alliance side
Thank you for your iron fist of justice. Though in this case, it may have been entirely too extreme. I don't care about the account being reinstated, I'll just make another one(unless you can provide a legitimate reason to why I can't create one?). I just want to avoid something like this happening to other users.
One other thing I can't quite understand.. If whatever I did in three or four world chat messages was so terrible to have deserved a perma-ban. Why hasn't someone like Bubblegirl, who is constantly polluting world chat for hours on end not banned yet?