I express my total disgust and contempt for this practice and its practitioners. There is never any excuse for it, and the law will never abide it. That's one of the rubs about auctioneer bidding. Third yet another issue that comes into play with auctioneer and staff bidding is manipulation. Manipulation is the ability of the person controlling the offering of the items to determine the moment of offering, and maybe even the description the item will be given.
Auctioneers obviously can control what lot goes up and when.
Ground workers frequently have the ability to determine the order in which items will be offered unless the merchandise has been prelotted. The point is that someone can hold a desirable item back until the crowd is weak and the money is gone. Then when it's put-up the result is a much lower selling price. If the person making the decisions about the selling order is the buyer, the result speaks for itself. This is why there is a whole body of law that deals with various issues that come out of the inside dealings people do for their own gain whether it's in estate settlement, asset liquidations, securities sales or auctions.