Try to trick someone into typing this with something like "omg, this unlocks a clue to the next expansion!!!11"
"/console blizzcon 1"
The next time they open WoW they will not be allowed to access the Options panel in the game or any console commands as it will be locked out. This must be a command that Blizzard used to eliminate tampering on the demonstration and tournament PCs in conventions.
The only way they can reverse the change is by opening their config.wtf and deleting the line.