I'm not convinced that the buyer will be unhappy when it arrives. The pictures are clear enough to show the cast nature of the surfaces and the weight is stipulated to be about 6g. To us it is obvious, but it's clear from this that there are a lot of people living in blissful ignorance. You see it all the time, as regularly featured on this thread. Buyers don't know what they are bidding on, and I'm sure that many sellers of the same don't know better either.
In the meantime, eBay rake in their fees and abrogate any responsibilities they should have. If you want to acquire a moral compass, I cannot recommend eBay's own brand, even with free postage from a company with perfect feedback.