Drugs like meth and crack are a pathology associated/linked to poverty. Idle hands being the devil's workshop etc. etc. Rural communities are now suffering the same pathologies as the ghettos. Figure out a way to solve the problem and you get to win a Nobel Prize.
Bears repeating. It's simple economics, a drug that can be manufactured cheaply in poor communities will become popular to manufacture in poor communities. Crack down on it enough until it gets expensive enough, and the kids will start sniffing paint, or drinking Robitussin, or any one of a dozen other cheap highs. It's not the substance, it's the culture.
I'm going to guess that a small-town environment makes it tough to get clean from drugs, due to the social stigma for addicts.