Basically a reference to the practice of combining two or more fast-food establishments into one building. Tricon Global Restaraunts Inc., owner of KFC, Taco Bell, and Pizza Hut, is one such engager of said practice, for no other reason I can think of other than to cut back on costs for building two seperate establishments so they can suck in more profit. CKE Restaraunts Inc. also does this, combining Carl's Jr. with Green Burrito. The problem with such endeavors like this is that the conflicting smells of pizza, fried chicken, and bastardized Mexican cuisine make for a revolting stench that makes me retch.
UPDATE: Though my views on multi-hybrid restaurants haven't changed since I last wrote this, I have made one exception. About 5 min. from where I live they opened up a KFC-Long John Silver's, and I must admit it wasn't a totally horrible experience. This is probably because of the fact that while they serve chicken and fish all in one roof, it's all deep-fried the same way (possibly with the same batter? ...NAW!) so there's really no rotten stench emanating from the kitchen other than the plesant aroma of fish fry. Plus it doesn't hurt that I'm a Long John junkie to begin with, and the fact Kentucky Fried Chickenshit shares the building is negligible, I can't even notice it. Also the place was really clean, although that's probably because it's still brand new, I'll wait and see how bad it gets, since every KenTacoHut and such I've been in looked and smelled like a cross between the inside of a compost bin with a dead amimal inside and a canister of bacon grease with rancid honey mustard dipping sauce.