They buy food from local farmers that they may not be able to sell at market because it's just too ripe to make it in wholesale shipping to markets far away, or it's too wierdly shaped, or just because they're the best cucumbers for pickling!
I'm so lucky to see these guys at farmers markets all over the Bay Area. Look for your local picklers at your farmers market. And if you want to get inspired check out the Happy Girl Kitchen story you can even buy some for your Christmas presents. So. Good.