It's a good idea.
Hell of a sight cheaper than dealing with the disease aftermath of sharing needles and cooking up in dirty conditions, for those of you who live for dollars and cents.
As far as the addicts go, well, one of the huge motivators to get clean, according to people I go to meeting with, is shame. Unfortunately, it's also one of the biggest causes of falling off the wagon again, too.
I have no idea if GETTING addicted to something is caused by a disease, a wiring defect in the brain, faulty biochemistry, or what. I do know that BEING AN ADDICT is a disease. One you got for life.