Why is prostitution illegal? The question can be answered better if posed differently. I think the better questions are: Would you want YOUR daughter to be a prostitute? Why?

This would make the idea much more personal. It would also help some people to refrain from labeling and name calling.

That is a flawed argument though as that form of questioning could be used to make almost anything seem bad: Would you want your son/daughter to be a Pornograpy star/drug addict/alcoholic/killed by a terrorist etc. If you personalize an issue to your own family it makes many things sound threatening and is a slippery slope to fear and control.