Looks like it's someone's personal RV set up. Saw it heading south on Rt 3 in Plymouth Ma last year. Erasing old images on my phone and this one popped up.
Ha, funny you mention it, I think i've been thinking about it since I first saw it. I'm guessing he must have a set of those really long ramps they use to load cars in the back of semi trailers. We used to use them when we'd load a forklift on the truck at a cabinet shop I used to work at.
I saw the same setup on a different rig on the highway when I left RTR in Jan. I think Lee is correct as I didn't see any ramps stored. At the time I was thinking this might work with a Jeep or Samurai. You'd have to do some careful measuring as the hauled rig couldn't be longer than 8' 6'' long since it sits sideways.