I think the high cost, but strong desire to achieve the lifestyle has contributed to the 'van-dweller' lifestyle.

I've gone from a Class C(Small RV/on truck/van frame) down to a Class B(typical Camper Van).

As you've said large RV's(Class A's) are lots of work, and less affluent people buying a used one, don't realize they're taking a problem off someone's hands. Namely finding a place to park it.