Direct your clouded gaze toward the Mexican Border. The marijuana business is not as idyllic as you might think. Not too many muchachos shooting each other over smuggled tequila, amigo.
My problem with recreational marijuana? Well in my vast experience in ordering members of the lower classes to their certain death, I have found that they use marijuana in large amounts, but have not thereby slacked off on their use of alcohol.
This makes them even more lethargic than usual, unenthusiastic, and diminishes their capacity to follow my orders.
Mexican violence is because pot is illegal not because of anything else.