Lets get the information straight. This is not simple graffitti or mindless vandalism, it's an immediately identifiable (if poorly-thought-out) protest - and the aviation people in that neck of the woods need to realise their "harmless fun" is impacting on some people lives so largely, that they feel the need to take this drastic action.
If the aviation people concerned don't take serious action to remedy the problem and recognise that our recreational behaviours can seriously impact on other people lives, then it will only get worse, and lives may be lost.
I wonder if the aviation people involved here would enjoy a jetskier blasting past their bedroom 30 times a day when they're trying to get some sleep after having done night shift?
A large % of our society sleeps during the day, and needs to have their requirements of modest noise levels observed.