Teleporting players on Survival Games and Capture the Flag

Since I started playing these mini games I have noticed a lot of players teleporting, running fast and spamming chat advertising their cheating client. They are always very cruel in chat and seem to be bad people. I have sometimes reported in game but I’m not sure if that does much because they always have different names.
Can’t there be some sort of anti teleport speed thing? Maybe admins could limit the amount of blocks you can travel in a certain amount of time.
PS: I think they know when they are about to get banned so they change names.