It's absurd you think puppies raised with cats would try to eat them without human intervention. That's far from the norm.
Not eating another human has nothing to do with the fact that we share a species and everything to do with the conscious psychological decision to have respect for the life of all highly cognitive beings which can live complex lives, and not arrogantly place my own need for survival higher than theirs...
But nuances aside, fundamentally I don't differ from the deer, birds, or squirrels in that I'm wired to do almost anything necessary to satisfy my hunger impulse. So I'm not sure how what you're saying makes any difference.