The counterfeit drives are definately showing up in every corner of the world. It is being tracked and documented. People are also fighting the issue - as there are too many victims who have suffered important data loss.
See: http://sosfakeflash.wordpress.com/ and also http://ebay.dybteam.com/ (for translation - languages and printing of articles).
Samsung name is definately a target of counterfeiters because of it's good reputation. People trust this brand name. USB Drive casings frequently have this name stamped on it.
As for eBay, our early research indicates that the problem goes back to 2005. Recent reports from ancient eBay members say that the problem of fake flash products goes back to 2003. It still exists there, almost all flash products are still fake. In May of 2008, victims of fake flash decided to do something about it. In April of 2008, approximately 37,000 listings existed daily - now it is down to about 8,000 and dropping.
At the end of August 2008, The FrankenFlash Project went public on the internet. As a result many fake flash sellers were shut down. Pressure was put on eBay and PayPal as they did little in the four preceeding months to address the situation. This issue is explosive and begining in November 2008 attempts were make to cut of the main site from major search engines.
The damage being done by these devices and the data lost is astonishing. Victims are not only end-users...
You will find the products also on internet sites around the world in the cheap price categories. Even on reputatable sites. The devices also end up in smaller stores through wholesalers. It is less of an issue in major retail chains as they deal directly with the major brand manufacturers, but then the prices are higher.
Major brand companies are taking some steps to address, by selling in sealed packaging (requiring much sissor work to open) and also by putting identifying serial numbers on the casings. Still, it is possible to produce counterfeits it appears that access to labels and packaging is not restricted at manufacturing sites - or so it seems.
This is unfortunately a subject few people are aware of, they will only find out if they become a victim and have suffered the consequences of using such a counterfeit flash device.