Walmarts, truck stops etc will vary by the location they're in. Usually the further away from large populations you are the better you are. Always good to double check before moving any equipment.
We were at a Lewiston ID Walmart, a very good one IMO and this Class A pulls up. He un-hitched his toad and parked it where the front end was pointed toward a culvert type thing, and then blocked the rear of his toad with his Class A. This was the same guy that set off his car alarm by rolling over the keys in the middle of night.
