When constructing his successful satire, A Modest Proposal, Jonathan Swift assumed most people would find the idea of eating (Irish) babies offensive and disgusting. And, in 1729, he was right.
I'm not so sure the same would be true today.
Ever heard a parent cradle his or her chubby baby and say something to the effect of "You're so cute, I could eat you"? I have, many, many times, and I don't think a disproportionate number of my acquaintances are cannibals. I even observed one mother jokingly(?) nibble on her 18-month-old's chubby thigh.
But, Joanna, you say, they don't seriously want to eat their kids. I guess not, though they, unlike some North Koreans, aren't starving. But nevertheless, popular culture is certainly sending us some weird messages regarding consumption and children.
Every Halloween, for example, I see more and more small children dressed as fruits, vegetables, bacon, hot dogs, cookies, etc. Of course, they look freakin' adorable. But the increasing popularity of these costumes suggests there's something appealing as well as permissible about conflating children with food. Even the police department of Mountain View, California, proved susceptible to this confusion.
It's not entirely clear whether the proliferation of "edible children" imagery is a reflection of society's interest in conceiving of kids as food or whether these representations are actually encouraging more of us to think that babies, not beef, is what's for dinner.
Freud would certainly have a field day with this topic, and I'll leave it to modern-day social scientists and psychologists to offer elaborate explanations as to why the prospect of eating children appeals to us. Perhaps we lay people would have better insight into if Hansel and Gretel had asked some questions before pushing that witch into the oven.