The ratings philistines probably denied Mel Gibson an extra scene in apocalypto where someone eats the flesh off a living human using a knife so that the last thing the victim saw as he died was his own kind eating his raw muscle tissue.
Apocalypto's sacrifice mode suffers from the Hide Your Children trope. The aztecs, Incans, and Mayans all sacrificed young children occasionally before the tribes were conquered.
Hardcore Christian: Mel Gibson?! YESYESYESYES!!
Hardcore Atheist: Mel Gibson!? NONONONONONO!!!