i think your numbers miss the vast group of prescription abusers. it is not "illicit" in the context of your quoted figures, i believe, but there are a hell of a lot of people impaired with the explicit assistance of the medical profession. And i think the numbers of alcohol abusers is an order of magnitude higher... is that a "drug" in the context you put forward? Do they need the same dollar output from the government?
It seems to cross all lines, i mean, a huge number of people can fit the definition you used at some point in their lives: people ranging from obama to rush limbaugh has had a go at alcohol or drugs... Not everyone needs government help with it, though, in my opinion.