Something's not right. Ebay does not answer on behalf of a seller. When you say "Ebay" says no discount is offered, do you really mean the "seller" says (through Ebay) that no discount is offered?

I agree with Bob. Don't pay until this is resolved. If Ebay issues strikes against you for not following through with the auction, you can argue that the listings state that shipping discounts are offered but were denied to you. The seller may be making his money off the shipping (since sellers get a discount from the published rates) and wants to multiply that times the number of chips sold.