This depends upon what you mean by treatment. For now, it could be very mellow - just take you out of the game and do some vocational training.
Why not offer it free of charge to addicts who want to participate. You don't even have to require they quit using (just not during the training for safety reasons). In some studies, such as those in Switzerland and one in Vancouver, the addicts quit on their own or with therapy once they find meaning in life that doesn't revolve around drugs.
I have no doubt that if such a program existed, with such a condition (you don't have to quit), addicts would be lining up to help get their lives on track. No need to incarcerate or forceably treat them when you can give the ones who want to quit a viable way out. Sure it would be an unpopular idea, but results from elsewhere in the world prove it works.
From a practical standpoint, it's a hell of a lot cheaper than incarceration too!