in one site to eat together, then have a campfire activity of some sort. There was a lot of loud laughing, playing guitars, and singing. It wasn't obnoxious, and absolutely fine during normal hours, but I was preparing to have to go over after curfew and ask them to keep it down. I've seen that happen too many times.

Nope, they completely shut everything down. They were respectful, and quiet when they should be. I was very impressed. If that's what people do while in a campground, I have zero problems with it.

The OP's request didn't sound like that, though. Maybe I'm overly judgmental, but I agree with you. The blaring music is almost never appropriate in a campground setting.