The problem is that he wanted to show it in classrooms.
Most teenagers aren't going to bother to go watch a documentary on their own time (speaking as a teenager, most of my peers probably wouldn't).
Also, not everyone is going hear about this movie. If it is shown in classrooms, way more kids will get to watch it.
Edit: Here's the relevant quote: "That's a problem for producer Harvey Weinstein, who had lobbied for a PG-13 label so he could tour the film in middle and high schools"
Most teenagers aren't going to bother to go watch a documentary on their own time (speaking as a teenager, most of my peers probably wouldn't).
Also, not everyone is going hear about this movie. If it is shown in classrooms, way more kids will get to watch it.
Edit: Here's the relevant quote: "That's a problem for producer Harvey Weinstein, who had lobbied for a PG-13 label so he could tour the film in middle and high schools"