One thing I can tell you from personal experience and a lot of observation is that an addict is not going to stop unless he or she truly wants to. Or if close-by friends just decide to repeatedly kick the ever-loving beejezus out of the addict - not exactly my first choice, but eventually enough whacks upside the head might convice an addict or two.
Just like Judd Nelson put Rob Lowe's head in the toilet in "St Elmo's Fire" (problem is, he didn't do it ENOUGH), suffice it to say that if a PA Crew member became an addict, JB and I would make sure that person was on a first-name basis with the toilet bowl deodorizers. :)