Cannibalism is cool. But remember, you are what you eat!
Actually I got a little cannibalism going on in Lone Wanderers too. But in that case it's more accurately, you are who you eat. Trying to mix up the story of the Windingo into the plot.
Which raises the interesting problem. From what I can tell the Windingo legion is really a prescription against cannibalism. The Alonguins seemed to be telling the story as if it were almost an infectious disease, if you eat a person you become a windingo- an eater of people, a monster that looks like us but is really a doppleganger. Considering that these were folks that spent a lot of time in Canada one could see that some winters were bad and Grandma could really just be a future snack. However, the social conventions against cannibalism would be directed towards maintaining social peace.
As the old joke goes, what is trust? two cannibals in 69.
And that could raise a problem for your characters. The social conventions of a post-apocalytpic world would probably stress that if you get so hungry that you have to eat a neighbor, you would be ostracized if not bannished from pleasant society. Frequent travel might allow a person to escape the consequences, but in the end, it's something she probably wouldn't want to brag about. Some drunk fuck in a bar could over hear it and think, "Hell that's what happened to my Elma, mother fucking skin eaters!" and pop you in the back while you're not looking.
Be careful!