There is parallel dispute about towing in ClassA section.
When some things can be personal preference and parking a dolly or trailer at campground sometimes takes effort, flat towing can set you quite few thousands $$ in brake system and bars, when that kind of money buys you new trailer.
When you change the car, you can still use the trailer with it, or resell the trailer for minimal loss.
Tow bars are mostly unsaleable on used market.