I was called to come and repair a decorative dry stone bench we built a while back for a conservation area. It was built well enough and looked quite attractive. It was just that it looked a bit too attractive to vandals. Being in a remote area of a park where only a few people ever walk it was the perfect structure to try to demolish without getting caught doing it.
It occurs to me that a special part of the park could be designed and built to be a 'Vandal Playground Area'. Dry laid walls and benches and cool features could be constructed within a well-defined concrete walled-in area. Those who felt the need to wreck things could come there at certain designated times and make havoc in a controlled environment where supervisors could watch and make sure no one got hurt.
After every 'session' (perhaps ever other day) those whole like to build things, or practice making attractive dry stone features, would be allowed to come and fix up the vandal playground area again.
There would be a small fee for both groups being allowed to come there, either to build with the stones again, or wreck what was built.