That also can be read as meaning the people who buy the drugs. If the demand is there, law enforcement can only harrass, never shutting it down.

An unimportant example of this is the market for Cuban cigars. I had no trouble getting them on assignments in the States. (They are, of course, legal in Canada).
I quit smoking years ago, so this is one expense I no longer have. The conduit I remember was from Cuba to Venezuela or Mexico, then to offshore oil rigs owned by U. S. companies and they by helicopter or supply boat to the mainland.