It is basic economics that the market in any product is driven by demand and the ability to provide a supply.
There is a demand for a cancer cure and people willing to supply that demand so there is a market in cancer cures. Do they work? I'm no medical professional, but, I would say most of the cures for cancer being sold are less than effective. This is simply an example of demand creating a supply.
There is a demand for recreational drugs and there is a supply. We call this the "war on drugs". Prescription drugs are widely available in this black market despite attempts at rigid market controls. Precursors for meth are controlled and meth is still available because there is a demand and there are people willing to supply that demand.
The United Nations has been battling illegal firearms manufacturing for years. When the British were occupying Israel the Israelis built hidden, illegal, factories that produced firearms and ammunition. Google "illegal firearms manufacturers" and read about busts of people illegally making guns here in the states.
As market controls increase, black market activity increases. As long as there is a demand there will be a supply. Period. Increasing regulations will only increase black market activity and create a "war" that makes the "war on drugs" look like a playground fight.