My wife and I buy Florida's Natural Orange Juice because it's yummy. But one thing that I find about buying it that separates it from all the other non-farmer's market goods we get is the picture on the cart--the grower of the oranges that they used.
Florida's Natural brand orange juice has a "meet the grower" plug advertisement that features the actual farmers that grow the oranges they use to make the specific carton that you buy. While it may not be the the sole reason I buy it, it definitely makes me feel better knowing where it came from. What if all my non-farmer's market goods did something like this? For that matter, what if my farmer's market goods had pictures of their farm, garden, bakery, etc.? Awesome. I'd be all over it.