That's a shame. APS would have been the only real venue to report activity like this. If you could contact the buyer you could present them with the information you found, but
ebay has made that difficult as well since they hide ids now for privacy.
I don't think that
ebay doesn't care. I don't think
ebay has the means to do anything about it under there current system. It's mostly automated and when you do get a live person they won't know anything about stamps to do anything about the situation. You might as well ask an art director to fix a plumbing problem. They need to hire some philatelic experts to overlook cases like above.
ebay's probably struggling to deal with all the other frauds and scams that plague the other categories - sports signatures, fake handbags and other "brand" name items that are knock offs, empty video game console boxes, cell phones, etc etc. The problems with stamps as a whole is probably really, really small compared to the rest of the site. I can't imagine trying to buy or sell a laptop on
ebay. I know the sellers of laptops are plagued by scammers from Nigeria and elsewhere. As stated before
ebay needs to hire someone who knows stamps. It would also help sellers to be able to list Third Reich German or pre-embargo Cuban stamps without fear.
As other stated before, the vast majority of
ebay sellers are excellent and problem free. Hopefully, people will shop wisely like one would do any venue for any product in existence. You'll always have bad sellers and fraudulent products in any selling venue. Who hasn't bought something at Wal-Mart or other big box store that hasn't turned out to be garbage? As for stamps, I've seen dealers at the APS show sell fakes and there's a well know auction house on the SAN that repeatedly will sell fake French colony overprints as legit even when the certs come back labeling the stamp as fake. Buyers can be taken anywhere. Hopefully, potential buyers do their research, make sure to read all the information in a listing and make sure a selling venue has seller protection and an amble return policy.
ebay does provide for the latter.