Back in the dim, distant past, there was a Calvin and Hobbes cartoon in which Calvin asked his teacher is they could debate the question about whether a murderer who ate his victim should be given a lighter sentence than one who didn't because the first was less wasteful than the second.

Unlike most carnivorous or omnivorious species, homo sapiens has mores about eating members of the same species.

Which, I suppose, is fortunate when you consider the male grizzly bear, who has been known to eat cubs so that the mother would go back into estrus. I mean, what a lousy pick-up technique!