It is not possible for the government to eliminate or even control marijuana. We can waste lots of money in the effort, however.
How long have we tried to eliminate crab grass and dandelions?
A weed is a weed.
Also, medical marijuana is far cheaper and safer than thalidomide, which can cost over $8,000 per month for cancer patients. The drugs both reduce nausea and promote appetite.
By your argument, weed shouldn't be legal or legal. It should be ignored. Tough to do with mind-altering substances.
Thalidomide is an antineoplastic. Cancer patients take it to treat their cancer.