Probably some green movement fanatics would look at our RV and say something like "That's not even close to the right way to enjoy nature." ....... and then change their tune radically when they wind up camping next to me in their tent in a pooring down cold rain and wish they could come inside.
By the way an RV with it's walls all the way around keeps your money from leaking away much, much better than:
A boat whose hole in the water can leak out your money only at the top.
An airplane whose hole in the air can leak out your money everywhere.