As usual, the US's approach to the war on drugs can be summed up in one word: yiiiiiiiikes.
Congress is incapable of doing anything positive where drugs are concerned. Heck, "positive" for the US with drugs is usually along the lines of "we're now crushing fewer orphans than last year!" Drugs are such a minor crime that it's crazy to make companies snitch for that.
Somebody out there might be having a good time without us getting a cut. -US govt. and believe it or not folks, existing “sin” companies like alcohol producers