I agree with YOU. If there's no practical use for an item, leave it in the motorhome. A future buyer will appreciate that you've left some practical items in it, and if they do not have a use for specific items, they can discard.
I actually did the same thing, but on a much smaller scale, when I sold a pop up camper. We had purchased portable drawers that we would pack like suitcases and able to move between the house and camper. Eliminated the need for suitcases/duffel bags, and helped cut down on clutter in a small camper. Buyer thought it was a cool idea and said it was thoughtful for us to leave behind in the camper.