Atheists accuse the religions that believe in God, because they supposedly make the believer a "stick-in-the-mud". But what they purposely omit to mention are the crimes of their own atheistic religion, which not only committed far worse crimes - even during the 20th century - but also reached the point of turning its followers into inhuman beasts, by torturing and....eating their ideological opponents! An act that not even the Papist Holy Inquisition with all its crimes had ever dared to consider....
I am, as you already know, an atheist. I’m going to give a long-winded response, because I’m not totally sure what you’re getting at, so will try to answer your question at the multiple levels it can be interpreted as. Also, I’m most likely losing internet access soon, so will probably be unable to respond to responses, so will try to cover all my bases.
At a practical level, there are many reasons not to make a meal of a person, or allow it as a social practice. A dead human carries many viruses that will be particularly virulent to other humans. To allow eating dead people would encourage hungry people to arrange “accidents” that would allow them to eat the dead body. And so on. But I assume you’re not asking about such things.
Next, I would say that there is nothing intrinsically immoral about eating a dead human. The human is dead, and presumably doesn’t care what you do to his or her body
http://www.agkyra.com/?p=163