I think there is a world of difference between offering a widow $100 for her late husband's Confente when she does not know what it is and has pulled it out of the basement for a garage sale and being the low bidder on an E-Bay item. The E-Bay item is business as far as I am concerned and my aim would be to buy low and sell high as a rule. It is in no way immoral to place a bid on what you know is a better item than a seller lists it as and hope like heck you get it. Someone else can always overbid you if their knowledge gives them a similar edge. This is not a charity. It is a business transaction. I've paid too much a heck of a lot more often than I've bought a sleeper.
I'd suggest to the altruistic that they contribute to Haitian relief (or the local food bank as my wife and I do) , not help E-Bay sellers get more money for an undervalued item.
Tom Sanders
Lansing, MI USA