I have seen those 1/6 and 1/12 listings on eBay. I am especially leery of the 1/12 auctions. Not for the bootleg quality, but that they may not exist at all. All of the sellers of the 1/12 scale humans have 0 feedback and all joined May 13th.
I had won 2 auctions for bootleg figma Windranger and never received anything but a refund from eBay/PayPal. Those sellers are no longer registered on eBay.
I also saw several new sellers of the monsterarts Jackson King Kong with auctions starting at $5.00, I think those were vaporware also.
I am not sure about the mentality of these scam sellers. It is not much money and eBay will surely get it back from them so why bother??