There are a couple of "Saturday market" type things in my town, where people have booths selling produce also, but from what I can see there is no requirement that they grow their own produce, and I suspect they just buy from SYSCO or wherever. They always have things that aren't in season where I live.
It's been fun planning meals around what we have (supplementing what we need from the store obviously)
It made me suspicious and I found myself thinking about bylaws for farmers markets. I don't think there are any; so I'm sure there is nothing stopping vendors from just reselling sysco products for "organic" labeled, "locally-grown" products.
Wish there was a feasible way of checking, for now I will continue to buy my goods from Whole Foods and Natural Groceries near me.