As I said, it depends on the drugs and on the girl.
In some cases the girls are pressured into it by circumstances or family, so it can be incredibly harmful for them. And, of course, men can easily cheat with prostitutes and wreck their families, or become so addicted to them that they cannot form normal relationships. So there are plenty of negatives.
Equally, in some cases the drugs are weed, ecstasy or coke and the dealers only really cater to partiers. Not everyone who takes recreational drugs moves on to things like heroine. In fact, I'd go as far to say that most people who indulge in "party drugs" don't go onto heroine.
Either way, both are quite seedy, and while I appreciate consenting adults should be able to do what they want, it's fair for people to say that they don't want it on the beach.