As I see it there are just too many things that are easy to break on a class A motorhome and and cause thousands of dollars worth of damage. A typical non RV owner will need several hours worth of instruction in operating common RV systems in order to prevent damage from ocuring, and I doubt most people looking for a long weekend motorhome rental would be willing to watch 8-10 hours worth of detailed how to operate videos, plus do a multi hour walk through of the coach.
On driving a gas class A, this may include concepts like watching out for tail swing, and tail dragging, off tracking, watching for overhanging limbs in addition to general handling, and driving techniques. Even after nearly 10,000 miles in my current coach, I still managed to lightly drag the tail pulling into a Buc-ees giant gas station in Texas a few weeks ago, I looked at that entrance, and thought, yeah I think I can make that, and guess what I was wrong and the trailer hitch dragged the concrete. It could have been worse, I scuffed the bottom of one of my rear cargo compartment doors turning onto a side street in Wyoming last summer.
On non driving stuff, you have things like operation of leveling jacks, some of which can twist the frame so as to pop a windshield out if operated incorrectly. Insuring the coach is level before operating slides, make sure nothing is blocking slide operation going in or out. (I just saw a photo the other day where a cargo door under a slide was left open when it was retracted, catching the cargo door and mangling the side of the RV). Then there is stuff like the fresh, gray and black tank operation, someone recently recounted an incident where an RV renter hooked the water hose up to the black tank flush instead of the water tank inlet, turned the water on and left. After a few minutes the black tank filled up with water, and backflowed up through the toilet flooding the RV. The list goes on and on, the need to be level to operate rv refrigerators, or else they can fail in such a way as to be a fire hazard, ....