To be honest for PP who are saying users do it to be edgy or cool, that's not my experience-
Most people are doing it be able drink without being "drunk", unwind, have "fun", "chat", have some "fun sex" afterwards-
It has nothing to with image, or being cool - hence why if you're not a user, it's unlikely you will know about it.
It's still has stigma and shame associated with it, if you are to be found out by someone who doesn't do it.
The "don't pretend to be cool by doing drugs" is an outdated message, in the circles op is talking about, i doubt anyone is really doing cocaine to "be cool or unique" -
And as another PP said, those who have "grown out of it" got sick of the expense, the come downs (which from what I've seen can make people very teary and upset), and lack of sleep- I'm told it's all good fun until you actaully need to go to sleep and can't!