Even if they are caught, they just don't care. They'll be out of custody in an hour or two, adn joking about it with friends. Lets just hope they move up on the path of being career crims, as they'll do time in gaol sooner or later, with big "bitch lov'n" boyfriends, eager for new 'cherry' meat.
As far as I a concerned, having them sit down and talk with with Vets etc is pointless, and would do nothing. In one ear, and out the other, off for a few bongs and some piss warm beer, stolen from Dad's fridge of course.
However, a 'gang tasering' for 'slacking off' on the cleanup of this and other vandalised sites, well that would be sweet. They would remember that.