Maybe being young, impressionable, wanting to please, wanting to feel accepted, and ignorant of the true danger ... leads to becoming addicted to hard drugs.  Maybe pimps and dealers primary focus on making big bucks quick motivates them to get others hooked.  Maybe poverty leads some to seeking whatever comfort that they can find.  Maybe the alcoholics and druggies will quit their addictions ... about as soon as the judgemental and self-righteous quit their addiction to the "high-moral-ground".