"pot and folk do not enjoy a "tradition"

I wouldn't bet on that. I remember once an article about an old uilleann piper who said that, when he was a lad, they used to use the stems of hemp plants to keep the pipes airtight. And they'd smoke the leaves as a change from tobacco, and cheaper.

And when it comes to folk music such as Blues and Mexican, there's a fairly long-standing association. As strong as that between beer and the English traditions.

There's not too much of a tradition of prohibition generally in folksong. Apart from the odd temperance song - and even they get stood on their head - viz what happened to the Wild Rover.