Nothing wrong with it, if the trailer carrying weight & rated hitch weight is followed. If the brakes & tires on the trailer are within specs. Also, if the MH hitch receiver is within the tow rating.
I see MH's towing enclosed car trailers also. There is most likely an up-scale vehicle inside.
I have a friend who tows his loaded 3/4 ton Duramax Diesel truck, with a golf cart in the truck bed, behind his MH. He is a good bit inside of all weight ratings.
"It is What it is."
2006 Chevy Silverado Z-71, 4X4, 5.3L, 3:42, 100% Amsoil Lubricated
2005 Jayco Talon ZX24-E Toy Hauler
Prodigy P2 Brake Control
15K Putnam XDR Class V
10K Equal-i-zer WD Hitch
Firestone Ride Rite Air Bags
2005 Kawasaki KLR650
2009 Doodlebug Mini Bike