Does it make sense that an app. with the sole purpose of sharing user-submitted videos would somehow be devoid of any questionable/suggestive content? Isn't it

Does it make sense that an app. with the sole purpose of sharing user-submitted videos would somehow be devoid of any questionable/suggestive content? Isn't it kinda Apple's fault for insisting that apps conform to their age guidelines, when those apps involve user-submitted videos? I mean...who lets their 12- to 17-year-old use an app like Vine? Do they honestly believe nothing bad might come of that?