I would like food to be rarer, but you have got to be kidding me with bringing up The Book of Eli when talking about realism. I'm not going to get into this too much, but you won't get "the Shakes" from eating human flesh unless the human you're eating was diseased. Nutritionally, human meat is no worse for you than beef. Besides, that was nuclear, this is zombie. Honestly the amount of food left kind of makes sense, assuming a high percentage of fatalities from the outbreak and ensuing chaos. The food is still there, perfectly good, but there's hardly anyone left to eat it.