From time to time we hear of sellers, usually newbies, who do not complete transactions.
If the buyer has sent payment, he can open an Item Not Recieved claim. If the seller cannot prove delivery, the buyer is refunded, the seller loses the fees he paid for the sale, and there is a defect/black mark on his selling record.
If the buyer has not sent payment, it is trickier. The buyer can leave appropriate feedback and Detailed Seller Ratings. These have an effect on the seller's abiltiy to list and sell.
Or are you talking about 'shill bidding" , an illegal practice in which the seller arranges to have bids placed to force up the selling price of the item? Normally in a shilled auction, the shill will drop out when the bid gets high enough. The shill and the seller do not want to 'buy' the item they want the bidder to pay his maximum.
EBay gives newbies some stupid advice. One of the dumbest is telling sellers to start an auction at a ludicrously low price, like a dollar, 'to encourage bidding'. It doesn't and the seller bears the brunt of the failure.
