I think the main problem is being in a position to obtain incontrovertible evidence that the card or drive has been hacked to read a greater capacity that it really is, and this is where h2testw.exe is worth its weight in gold. Far too many people write it off as bad luck and don't bother trying to recover their money, and the sellers are aware of this, which is why they continue to sell their dodgy cards until sufficient buyers complain so that eBay eventually shuts them down.

It might only be a few dollars, but if everybody who was stung by these crooks lodged complaints with Paypal and included the report from h2testw.exe, not only would they get their money back (instead of the seller) but they'd be shut down far more quickly than they are at the moment so fewer buyers would end up being ripped off in the future.

The other problem is that most buyers don't use more than the first few Gb of their card's capacity for some time, so it's often weeks or even months before they realise they've been ripped off. This is why I immediately test every high-capacity card I buy the moment it arrives, especially because it's not always only the cheapies which are counterfeit.