I can't see many dealers using dark markets above plausible personal use amounts since you get caught importing dealable quantities you are screwed, dark market or not (And the mail system will get a % of buyers). You might have a $1000 per week habit or be a $1000 per week dealer. Who's to say?
Sometimes the state apparatus is precisely the one committing the most heinous crimes. (with impunity!)
> https://en.wikipedia.org/wiki/Allegations_of_CIA_drug_traffi...
> http://nsarchive.gwu.edu/NSAEBB/NSAEBB2/index.html