Today, July 27, 2010, the appearance of actual trading on the CME is misleading. Same buyer and seller for all the cheese.
Butter was a similar story. Except that, the seller appeared to be Daisy Brands. Here is a link to Daisy Brands product list: http://www.daisybrand.com/products/index.aspx
As anyone can plainly see, Daisy Brands would have to go out and buy butter to sell on the CME. This is not a rare event.
Obviously, Daisy Brands has an interest in the price of cream at the farm, and guess what, that is what brings Daisy Brands to the CME.