Scott, I am the person who collects money for the Wigger Group. But we always allow people a "test run" of the area before they need to pay. So please come out and see if it's something you want to be a part of. If not, no sweat and no need to pay.
Our dues are $30/yr, which allows you to camp every weekend but two through the end of September and also two potlucks during the year. Our first potluck this year will be this Saturday night. The Wigger funds will be buying briskets and sausages and everyone else brings a dish to share.
We are trying to organize a swap meet for this weekend. They're usually pretty informal affairs, being pulled together on the morning with the least wind, so I can't really say whether it would happen Sat or Sun. But if people have their gear out there, of course they would sell it anytime.