This question bugged me since I first learnt at the age of 3 or so that I wasn't allowed to watch some movies my parents watched. I never understood the reasoning behind hiding the reality from children.
Let's take a look at two games: World of Warcraft and Playboy: The Mansion.
World of Warcraft features role-playing a serial killer. You literally kill many thousands of all kinds of creatures and sentient races, including humans.
ESRB rating: T, 13+
Playboy: The Mansion features role-playing the businessman who founds the Playboy magazine. You get to build relationships with people, including sexual ones. You don't kill a single person.
ESRB rating: M, 17+
So, murdering thousands is fine for 13 y/o while building sexual relationships with other people is not? I've always thought that serial murder is considered bad in our society and sex is considered one of the best experiences a human can have. So why did our society get it all upside down when it comes to video games, movies, books, etc.? Since when are woman's breasts worse for a kid (who, by the way, has seen them multiple times when his mother fed him) than cutting people in pieces?
Not a sarcastic post (well, maybe a bit), I am genuinely curious what causes people to view nudity worse than murder.