I ran a group of auctions almost a year ago, some with $2 shipping and some with $4 shipping. Amazingly, the base bids were fairly uniform. I have concluded that a large percentage of auction bidders do not take shipping into consideration when they place their bids.

This surprised me, since I always take shipping into consideration when bidding (and will not bid when shipping costs are undisclosed), but I also realize that these same people serve on juries and vote in elections. In other words, when we see so much irrational behavior in law and politics, why should we be surprised by irrational behavior in the economics field as well?