They are called, 'Pharmaceutical Companies', but that's just a cover-name.  Regrettably, they have become legalized Drug Pushers:
Most people get their first introduction to opioids with a Doctor's prescription for pain treatment.  That's the root of the scale of the epidemic.  The Drug companies claimed that their modified oxycodone (time-release opioid) was Not Addictive.  (This is like the tobacco companies claiming nicotine cigarettes are not addictive.) 
Many Doctors simply won't prescribe cannabis-derived substances for pain treatment - even though its not addictive and has almost no known harmful side-effects.  Why?  Because the Drug Companies can't patent and thus make windfall profits from a natural plant that's already being used.
So instead of opioids being the 'last resort', its the first choice after over-the-counter drugs.