The plural of anecdote is not data. What you are saying is that there is a correlation, but the causation could be any number of tangentially related things. e.g. a self re-enforcing subculture, predisposition for substance abuse, or tainted sourcing.
Even with causation something is amiss with the generalization as presented. If a chemical amplifies an experience, and a person experiences a peaceful hippie experience, that doesnt mean the drug made them a hippie, it means the experience did. The same chemical in a violent experience could exasperate violent tendencies. Pinning "I know some people that fell into a culture" on a chemical is very much on the wrong side of nature/nurture and ignores set/setting.
