Thierry.. if no one bid until the last minutes in any auction anywhere... you'd see alot less quality stuff being sold and maybe a lot less auctions as well.
an auction is a two-sided affair: buyer & seller. Early bidders give the seller an assurance that what they are selling will not sell for peanuts, while late bidders stand there ofering peanuts (well, sometimes :- ) )
as a dealer, I want all the early bidding I can get, as abuyer you're looking for the cheapest price possible.
Ebay cuts the clock off.. Bruce and I do not and while cuts the clock on Sundays, they don't on quartlerly auctions..
it's a real mix of reasoning on both sides of the business