Just a few minutes ago I was thinking about old-time armies and how food used to be a problem for them. Why, I don't know. I also don't know why that thought led to this one: that a tactical advantage in that kind of situation to having an army of cannibals would be that food becomes less of an issue - your soldiers can just eat the corpses of their slain enemies. Again, no idea where the hell this all came from. My brain is weird.
Hell, they could eat the corpses of their fallen comrades, too.