Not crazy at all...
I have seen small vehicles with huge overloaded cargo baskets....
My thinking is that you would be limited in RTT's choices..
We got the Autohome Columbus for this very same reason...and easy of deployment / put away.
Although, not any time soon if we needed to I coud pull the RTT from my rig and put it on my wife's Saturn.
No,it is not a sedan but a much more smaller profile vehicle...
Hell, I think I could put my RTT on top of Co. Vehicle.. a KIA Soul.
Just keep in mind the weight limit of whatever load bars you with...