Joe, I agree that your 'community' is probably where the songs were first sung traditionally (or should I say non-commercially), but most were collected later in what has been called 'traditional village community' (or retirement homes) by former members of such occupation groups.

I probably should have added railroaders to my list too. Not many were collected directly from such occupations groups, except in the islands of the Carribean from stevedores, cane cutters, and fruit gatherers.