I am not sure why they do it but I can tell you why we do. We have sold on eBay for several years. One of our strategies when trying to drum up interest is to use a percentage of the items as loss leaders. You could say we simply treat the cost like it is a marketing plan. By doing this it generates word of mouth, feedback we can use on future listings, new customers, residual sales, free advertising for our website, and market testing to help set price points and so on. I doubt they are profiting much if any. The cost to even take payment using paypal would eat up 30% of the $1.00, not to mention the eBay fees.