Here's the thing about American film ratings systems: They've never been particularly consistent or logical.
Consider Kate Winslet's breasts, which will be revisiting a theatre near you beginning this week in James Cameron's 3D reinvention of Titanic. Access to a teenage audience (of the sort who could best appreciate Leonardo DiCaprio's distinctly unthreatening masculinity - yep, this is pretty much how we have Justin Bieber) was crucial to Titanic's unprecedented box office success.
But that PG-13 rating doesn't quite jive with Winslet's nude scene (this isn't Europe, people). Framing this nudity in the context of art ("I want you to draw me like one of your French girls") allowed the film to just squeak by - and allowed parents across the country to drop off their middle-schoolers at the theater.
It's this system - built on a shaky history of capitulation, defiance, and flexing to accommodate cultural norms and profits potential - that bestowed a PG-13 rating on The Hunger Games, with its graphic depiction of violence against minors in a fictional world, while Bully, a documentary about violence against minors in our world, warranted a dismissive R.