I applaud the idea, but I can't imagine an American city that would let these hang around for long. Police are already pretty "great" about making sure people can't sleep in their cars overnight anywhere.
And then you want the owner to pedal this to an RV dump station? That's simply not happening. Best case, they park it near a rainwater sewer drain and literally dump their shitpile in the road.
Sadly, what we're really missing is the foundation. We're going to need governments to step up & start making vanlife legal. Enable driver's licenses & IDs without a permanent address. Create parks specifically for people living in vehicles. (Of course, the better solution would be to make living more affordable, but we're currently heading in the opposite direction).