Originally Posted by RockDodger
They prefer you check with them first, but if you arrive in the middle of the night at a store that isn't 24 hours, they usually don't have a problem as long as you don't hinder customer traffic. Just a heads up; in some areas the police may knock on your door to do a safety check. You can read whatever you want into that, but I usually take their intentions as honorable.
Have not experienced the police knocking, but I've only done it a couple dozen times. I have to say that would surprise me with someone knocking!
As far as advice too since I'm posting again on this the larger wal-marts are better since you can find an out of the way corner. The small older ones can be hard to get away from the entrance. There can be problems with big trucks idling or running loud generators overnight.
I have seen Wal-marts where people are obviously camping in the lot, but I've just used it as a place to stop for a night while on the way.