The documentary Very Young Girls may change your viewpoint. In particular, the median age of [corrected: entry into prostitution] in New York is 13. Typically they are runaways or neglected/abused children kept in 'the life' by a combination of threats, violence, and pseudo-romantic attention. A John caught by police is sent to John school, with the possibility of getting off in a few months with nothing on his record. The girls are often times tried for prostitution as adults, even when they are held against their will, even when they're below the age of majority, even though were it not prostitution they would be, legally, the victims of statutory rape.<p>Much of this is possible because perpetrators have the easy out of saying that 'they didn't know.'<p>In general, I think that you're right, but there's a loophole here damaging enough that it might merit a special case.