Ok, if you promise in return that you read my posts more carefully.

I didn´t say it was the reason for these things to occur, I said it was the reason why they are likely to occur more frequently in the sex industry than in other industries (e.g. are there unions in the sex industry?).
The reasons for exploitation and inhumane behaviour are typically greed and power issues (and if we look even deeper, the reason for greed and power issues is fear) - that is the same for all industries.
He/she would have to be an adult to work there, so there would of course be no course of action on my part.
Just like with any other job I would warn him/her of the general problems and risks that come with being an employee, and I would try to make him/her more aware of the particular risks that come with the particular job they are picking.
Thought process?
"What will he/she do when she will be too old for this job? Does he/she have a decent education so he/she can work in that job later?"
"He/she´s really picking the hard way. I wonder whether and how he/she will be talking to others about his/her job, what the reactions will be, and whether he/she can live with the responses."
"He/she could have chosen much worse, e.g. if he/she had decided to become a soldier."
I still don´t understand the question.
By definition means are not even supposed to justify their end.