Obviously there is no universal rule that is followed by all campgrounds everywhere, except the Golden Rule, which is, "He who has the gold, makes the rules."
In other words, a campground owner is going to run the campground the way they see fit. As many campground owners seem to be squirrelly antisocial blank-holes on power trips, your mileage will certainly vary.
If there is any question, ASK before you sign the paper and pay your money. When you don't like the answer, put down the pen, walk out the door, and mosey on down the road.