I think this gets back to fillyjonk's post. It's disheartening to realize that Twilight is popular because readers find its model of romance appealing. But the reason why it's appealing is that there's so much cultural reinforcement for that model in general. It's not like readers are only exposed to healthy models of relationships and then read Twilight (or Heinlein) and proceed to embrace that model.

Trying to restrict access to Twilight in the absence of recognizing that our culture is soaking in problematic relationship models is basically a form of scapegoating.