I do agree it doesn't change the rental market from the owner's perspective. But is Disney 's concern the owner's perspective or their perceived competition?
People also tend not to be as upset if Disney is competing with their ability to get rooms for some reason. It is the sense of unfairness of commercial rentera that seems to rile people .
Many of the anti- rental posts don't seem to have a problem with points returned to Disney from concierge collection, MMB,
Disney cruise, etc which has the same net effect on them.
I would assume Disney would be able to rent out those rooms at much more than the dues cost, just like a renter does so some of the other losses could be offset. Clearly one would have to go through the numbers to see if it was a net positive for Disney or not.