Larry wants a Playstation2. Other people bid the rest of it, so it's not really his money. Of course it IS his money, if he wins, but the psychological ramifications from this are very profound. If a seller opens an item for far less than he is willing to accept, he runs a very big risk. However, Lowballers by their very nature force them to do so.
Snipers can actually raise the price a fair amount.
Time to ponder the Univserse. If you are a sniper, and know about an item that you want days in advance, then you have time to really examine the item. You can change your mind over and over again. You have time to e-mail the seller with any questions. You can read the description thoroughly and understand exactly what you are bidding on.