Once you give a population a mind altering substance (or various) you start seeing the development of new groups. (Hippies junkies and alcoholics). It affects an individual to an extensive degree - enough to notice a stereotype. Its invalid to simply ignore such things.
I also never actually put drugs in negative light. Its a fact that many slack off and be demotivated when under the influence. A minimalistic lifestyle would be a product of of finding spiritual inner peace - another stereotype which is true to a certain degree.
So yeah. ROCK ON HIPPIES