Is this fully true? Using wikipedia as an example, lots of people go away if their vandalism is just quietly reverted. Make a fuss, it becomes a contest, but quietly just undo it as a normal part of a days work, and they get bored eventually.

To my knowledge, actual "tagging" teams are more interested in the bragging rights. If you tag a shipping container, it will eventually be removed. But your incentive isn't to leave a mark: your incentive is to just do it. Either way, this is a situation where both posts are technically correct, in my eyes: tagging teams will probably start to seek unmarked territory, whereas these "extremist" tagging attacks will be discouraged.