Actually BOTH of these movies involve cannibalism. The first one is the best treatment of the Ed Gein story, the guy who inspired both PSYCHO and THE TEXAS CHAINSAW MASSACRE, which should give you some idea of how broad the statment "based on a true story" really is! MOTEL HELL is complete fiction and is based on the old hillbilly barbecue theme.
Whe the world goes to war,, blows itself to hell & back, and life on the surface becomes impossible, what do ya do? You dig down deep in the earth and look for the most plentiful food source, your fellow survivors!
If that kid you adopted from the Ukraine doesn't work out just stick him under the stairs like the couple in this Wes Crave flick do. You just have to remember to feed 'em every once in awhile or they'll turn on each other in order to survive.