This do boggle me a bit yes, being a european and all. Over here partial or full nudity get a 15 years rating, which is a fair deal. If its uncovered straight up sex involved it get a 18 year rating straight up, but this is also fair. Cussing and such isnt frowned upon at all, its actually almost expected in the 15 years rating bracket. We are a bit harder on violence than the US though, making us pretty much opposite to the US in this department.