Read a book by a defector who claims people there are eating tree bark and grass to survive. How do they have the funds to get this stuff?
I have heard that North Korean diplomats routinely traffic narcotics, including methamphetamine in their diplomatic pouches to raise hard cash for the regime. Factories inside the country make the stuff, as well as counterfeit currency to launder in, and undermine foreign countries.
NK gets foreign currency by exporting weapons and meth —of course they counterfeit foreign currencies, primarily the US $100, and the Japanese 10,000 yen note.
This is a guess, but I’d say that aside from Mexico, NK has the biggest meth operations in the world.
Read the story again. I've added some to the following line to clarify it.
The North reportedly began producing them (drugs) in the early 1980s to earn the hard currency for the regime (by selling the drugs outside NK).
So the production of hard drugs was encouraged by the government and became wide spread. The equipment and know-how is now also wide spread. Producing drugs is probably cheaper than producing food.