Has IQ's just dropped sharply while i was away?

I am interested in an item for sale on the Ebay auction and have noticed that there are three people who have been bidding on the item over the last few days of the auction. Between the three of them these same three people have taken the start price of £16 to £170 with a few hours til the auction finishes. Now call me stupid but would it not have been more economical to have began the bidding in the last few hours and maybe keeping the price lower? Not sure if its relevant but they are all women ;-)