Cannibals in real life have the shakes..
Minor correction: Cannibalism CAN transmit a prion disease like K-JD (also called BSE in cows, or "mad cow disease"), Kuru or other diseases that tend to share the common symptoms of loss of motor control (IE "shakes"), eventual paralysis, ect. But that requires brain-to-blood contact with an infected person. It did happen among some cannibal tribes (the kuru outbreak ended the practice, and almost ended the tribe), but I wouldn't say it's common.
Though did anyone note the minor cross-reference potential in-joke with the guy by the Vegas gate? talking about his dad the butcher and his competition giving people the shakes? I found it funny in a gruesome way.
Also, on the topic of other movies, I think they're all drawing from the same well. Fallout was essentially the unofficial followup to Wasteland, which drew inspiration from A Boy and His Dog and Mad Max (which in turn also drew inspiration from A Boy and His Dog). Book of Eli is just one more in that long tradition.
You know what I want to do? try tracing the true originator of the genre, Wasteland was probably the first post-apoc video game. Mary Shelly's "the last man" might well be both the first sci/fi and first post-apoc book, but it didn't have all the elements (raiders, ect) and lacked the atom bomb because it predated the manhattan project by over a hundred years.
The problem is most of those early works either lack the elements of the fallout-style post-apocalypse: Raiders, radiation, scavengers, ect. or are of the "cozy catastrophe genre where the focus is on a small invariably W.A.S.P. types rebuilding society without the hardscrabble survival elements that define the genre as well.