They have brought the price up themselves, I watched this auction, and IMHO the starting price was fair and cheap.
Similarly, about a month ago I sold an SX32 Pro on eBay UK for £410.00 ($735.00), but the starting price was only £19.99 ($36.00)... it's these crazy bidders that inflate the prices!
(Although having said that, I've seen plenty of Amiga auctions where the starting price is very high and not far off the vastly inflated final price)
As someone has said previously, it indicates that a huge demand clearly exists for Amiga hardware.
Steve.