A few reasons ....the motorized is alot easier to use and roomier though not the headroom...dinette stays put, has AC and a shower and bathroom...gets 14mpg (about what my minivan does hooked to the uhaul), beds longer and it has a fridge
. If dry camping
it also has water and lights
but not the ac......It's just easier to hop in and use.
Really do like our uhaul
but right now wont be using it.......down the road, maybe a 16 or one of those cool parkliners (if you can get it without all those crazy cupboards).......Bruce