things may have changed on ebay since my laptop battery problem, but I did report it to ebay as a FAKE and yet I was told to pay for return shipping and it most certainly was not free. I had photos and even some linux syslog dumps to show ebay (not that they'd even know what to do with such data). they still told me to send it back via trackable mail and there was NO voucher or prepaid shipping label sent to me.
it was at least 2 years ago, though, maybe even 3.
It all depends what you report with eBay.
If you report an item that does not work, it's easy, you will be refunded.
If you report a counterfeit item, it's much harder to get a refund.
Years ago (5-6 years ago ?) I remember filing a claim for a fake Sandisk CompactFlash card. I got an e-mail from SanDisk confirming that I've been shipped a fake card, but PayPal wanted me to hire and pay a legal expert (!!!) and to ship the card to China back to the seller.
The worst thing is that the seller didn't even understand why I wasn't happy... "why aren't you happy, the card works no ?"
I have no problem with buying cheap stuff from China, I just want to know what I'm buying.
It's the same with FTDI here, I don't care if Chinese manufacturers make binary compatible chips, I only care about people writing FTDI on chips which are not made by FTDI, and shipping those to me. But even when that happens, I'm not responsible for it, I can't check the whole supply chain.