"banishment" has a minimal affect on the problem at hand. Villagers have few, if any, tools to fight illegal substance activities in their villages. What these villagers are doing is to protect their own from deadly illegal substances. I think it will some affect on people who live in the villages who chose to conduct illegal activities which cause death. "Banishment"is just moving the problem from one area to another. 
I think what needs to happen is to have a program during a children's early years in school explaining the affects of illegal drug use and the effect it has on one's future and life. People need to know there is help for addicts but the desire to quit has to come from the addicts themselves. You can't force anyone to quit but you can let them know there is help if they want to quit. 
This is not a "local" problem" but a statewide and nationwide problem. 
Condescending attitude toward any ethnic group is not helping. It affects all ethnic groups.