Chuck,
The reason you owe the person selling the butter pats $15 for each of the 6 you bid on is because since you bid $15 on 6 of them, the seller only had six, therefore inorder for someone to outbid you they would have to bid a minimum of $15.01. Dutch auctions a different than regular auctions because if you bid on the entire lot, your bid price becomes the new high bid price. There is no proxy bidding in Dutch auctions. Hope this helps.
Luke R-3867