Bitcoin "Powered by drug addicts"
That's not a bad surmise. The darknet markets aren't going away any time soon and will be the mainstay of Bitcoin until it hits the big time.
I have a theory that the web in general was massively helped by people wanting to watch pornography from the relative anonymity of their own home (no embarrassing renting of VHS/DVD's any more) and from there sprung the commerce driven web we have today.
So nefarious services will continue to help Bitcoin stay alive. I have no problem with people buying drugs from the privacy of their own home if they do their research and use them wisely/safely.