I think it has a lot to do with respect. Campers typically respect each other and come together in a semi-communal situation to let their kids play together, visit the same beach, share campfires, bath houses etc.
Campers are usually willing to "give" overwhelmingly. Their time, goodwill, resources, help, parts, tools, etc. Sadly, this is in contrast to much of society today when we are back "in the real world"
It's when someone wants to "take" instead of asking or being courteous that we tend to snap back into defensive mode that many of us are in with our day to day lives.
Whether it is taking our space, our peace, our sleep, our view, etc, it seems it is that unpleasant, forced switch back into "real world mode" instead of "vacation mode" that seems to really stir up resentment in many folks.
Just like a previous poster said. It is more like old times when everyone felt like being good neighbors. It's when that temporary reprieve is broken that people get upset.
Be polite and respectful, apologize if your kids get noisy or were talking too close to another camper's window at night (yep, guilty!) and more often than not you will be met with ample amounts of courtesy, flexibility, and even forgiveness, just as we do for others.
BTW, the camper lied to us when I went over to apologize in the morning. He said he didn't even notice and it wasn't a problem. It was only about 20 mins before I noticed where the kids were standing, but still...the fellow was very understanding and I did call them over when I realized it.
An example of how courtesy begets courtesy, as many have similar stories.
Okay, you can get up off my couch for now, our session is over. LOL!