I think the fact the use and abuse of legal opiates are much more common (abuse is estimated an 10% of US population each year) than heroin (use is estimate at

I think the fact the use and abuse of legal opiates are much more common (abuse is estimated an 10% of US population each year) than heroin (use is estimate at only 1.6% of US population even once during their entire lifetime) explains this. Heroin is made much more dangerous because it is illegal and therefore of unknown potency and purity.