Loud, self-centered people.
Once, we were camping in North GA. We reserved a spot well away from people in a group spot.
A church group had dropped their gear in the spot next to us.
Not long after, a Scout troop came in and started making a fuss about how the spot the church group was in was actually theirs and proceed to set up camp. The church group showed up a bit later to find the Scout troop in their place.
I went to the ranger station and reported what was going on. The Rangers sorted it out by making the Scouts move to another spot. After that, the Scouts were super loud all of the time. At one point, a kid had 2 plastic soda bottles and was banging them together like Boombas.
I confronted the Scout leaders and they said if we din’t like it, we could leave. I reported this to the Rangers as we went for a hike. Went we got back the Scouts were gone. When we checked out, the Rangers thanked us and said the Scout Troop was banned from the park for a year.
Another time, we were camping in North Alabama. About 2 in the morning, I hear the unmistakable strains of “Free Bird” from a few sites away. I got up and walked over to the site were 5-6 guys, 18-19 years old, were sitting around a fire, truck stereo cranked to 11. I calmly told them to turn off the music or I would call the local sheriff or they could explain to the cops why they were drinking beer in a State park. Didn’t hear a peep the reset of the night.