Except the movie is about the line between an R and an NC-17 rating. Kids under 17 are not supposed to be allowed into an R rated movie without an adult. On the other hand, NC-17 rated movies are not shown in most movie theaters. So by giving a movie an NC-17 for, for instance, depicting a woman receiving oral sex (like Blue Valentine), the MPAA is effectively limiting what movies adults can see, rather than protecting children.
