This past wkend attended OAKS, PA RV show. I saw on several travel trailers a rear folding "cooler" basket. It mounted to bumper (not into 2" receiver) and had a bracket on bottom to mount spare tire....
Sounds like you may be referring to the LCI rack used by at least Keystone and Forest River. It is not supported by the bumper, there are frame mounted brackets above the bumper. Mine has a weight rating of 225 pounds.