Comparing a profession to the most addictive and harmful drug known to mankind (or at least close to it!) is an absurd strawman.
The sex industry is terrible for everyone involved; it's addictive, it ruins the lives of the girls and men who work in it, it spreads dangerous diseases, and it doesn't contribute to the advancement of our society. I can't imagine why anyone would support it except out of a sadomasochist curiosity.
I suspect (ironically) you may be too sheltered to understand why the sex industry is so harmful