I have always found cannibalism in general an interesting subject. We all take to the reality cannibalism is eating the flesh of one's own kind. From what I have seen, it is much more complex than that. Cannibalism is usually common in times of famine or part of foreign culture where it is acceptable.
In terms of animals, it is always from the result of starvation, nothing more. Polar bears, for instance, their food supply as well as their habitat is being destroyed. Like any mammal (humans included), in times of desperation, they will do everything and anything to survive. Even if it includes eating their own cubs. With this known, I have come to fully respect the existence of cannibalism.
However, in Feral Heart, the act of cannibalism is different. I like cannibalism practices in role-play when it is played out in a reasonable and creative manner that derives from its purpose. From what I often see, cannibalism is a trend. It is something cool to do in a role-play or give that edge to an evil-orientated role-play. Not to offend anyone who does this, but I just cannot bring myself to respect this at all.
Added, this could be why some people look down upon "cannibal" role-players. When people think something is cool, it spreads in all kinds of ways. The people who create a good premise and the people who like to be with the popular crowd. Since people very often see the cannibal trend in an unacceptable shade of light, they will often come to criticize anyone else who has a cannibalistic character. Basically, stereotyping.
I dislike that cannibalism is so downplayed. It is more serious than people think give credit for, like killing or robbing valuable property. For anyone who gives cannibalism dignity to continue on with their characters, continue to grow. Happy role-playing to you. For those who just play off cannibalism as a fad or the next cool thing, please cease it until you understand cannibalism itself.