Well, with laws in place, 5-year-old children would be allowed to drink alcohol and shoot heroin, but that is hardly the case and will never happen, so this is a moot point, because those laws will never be passed.
The reason car companies allow an individual to own a dealership is because these people BUY the dealership franchise for massive amounts of money (hundreds of thousands) and because the money they bring in and pay Ford, Chevrolet, etc. FAR ourweighs the loss they take by outsourcing (and yes, it IS outsourcing) their business. These people sell hundreds if not THOUSANDS of cars per year, a certain percentage of which they pay to the auto companies. This would not be the case with a lone person who has one flipping robot. The paperwork alone and the people they would have to hire to do the biling and invoicing, etc. would be enough to prevent them from renting singular robots from individuals. If anything, they would rent/buy them from a company. This will not happen, ever.