It is IMPOSSIBLE to ban a single person from anything on the web, you can only ban the stuff they use to surf, i.e. thir computer, their server, their IP block. In this case, Bungie bans their .NET passport. All they have to do is make another one. Unfortunately, the time it takes tham to make another one is too short compared to the time they have with that profile. Once the mods can ban, the time they have spamming will last all of five minutes, then they'll have to make another profile. This is no fun, so they'll leave.