I have alway's found it rather un-nerving, that a local government can legislate who may shop at any store. I can understand having ordinance's that restrict parking for longer than a specific timeframe, but to specifically exclude shopper's who happen to drive large vehicle's is bordering on blatant dicrimination.
What if they said, "no red car's can shop here", or only American made car's can park here.
Of course, it has been the case that some driver's don't care about the local surrounding's and dump trash and other thing's on the parking lot. They figure, "let someone else clean this up".
Shortly after the new Supercenter opened behind the regular store in Evanston, WY, I saw a guy throwing pallet's out of his trailer on the edge of the lot. He looked around then drove off. Guess he figured he wouldn't be back there, so it was OK to do.
These people get us thrown off more lot's than anything else.
As for sleeping on Walmart lot's, I personally don't do it. I plan thing's a little better than that. They are grocery store's, not truck stop's.