We had a really loud and late neighbor one time that I recall. Think it may have been in a state park. They looked like a group of friends getting together, nonthreatening, I went over and asked them to tone it down. And they did.
I have seen a CG trashed by people. Blackwater State Park in NW FL, we got there right after the 4th of July. The place was a mess, watermelon rinds all over the place, trash cans overflowing and no sign of any park employees. I later found out there were supposed to be a couple of college students as CG Hosts but they went AWOL.
I've recently discovered that FL Parks have a very hard time recruiting CG Hosts for the summer, one of our local parks doesn't have one. The winter? People lined up 10 deep for the job...heh. Wonder why.