But it’s the seller’s fault in the first place.
It’s against eBay rules to use eBay to find buyers for deals outside of eBay.
And I think they rarely make a good deal either. Why else are people offering to buy it outside of eBay? Clearly they must believe they wouldn’t be able to win the item through \"ordinary bidding\". So a seller with some brain cells should ignore all offers, and let everyone bid. I’m certain that in most cases, this will give the seller a better price.