Another thing that can be abused is the "honor" system of checking into a CG late at night. They may have a "find a site and see us in the morning." We were at a KOA 2 summers ago in the Brandywine area (Philly) and a motorhome came in around 10p (the office was closed). The guy circled the CG a few times and then settled on a site across from us. He had some issues getting settled, DH and my brother in law went over to help, turns out he borrowed the MH from a friend so he wasn't real used to it...we got them settled...next morning before the office opened, they were gone! We are sure they did not pay for their site. So you can have folks who arrive late and skip out early without paying for the site.
We have never stayed at a Walmart and never say never...but DH always checks for a stopover along the way if we need to stop. We stopped overnight at a beautiful state park in Ohio on the way back from Goshen. It was only $25. We had electric, but water was just across the road. By stopping at an official campground, we were able to not only open slides and set out chairs, we had a campfire and cooked hot dogs with 3 other Heartland owners...and had a great time. Can't do that at a Walmart or other "permitted" stopovers.
If people continue to abuse, those privileges will be lost. Haven't we all seen a circumstance where privileges were revoked because of some sort of abuse or mis-use?