That'll stop a lot of the problem but not all. A friend's company have massive counterfeit problems with Beats by Dre headphones. In their case it's people buy

That'll stop a lot of the problem but not all. A friend's company have massive counterfeit problems with Beats by Dre headphones. In their case it's people buying genuine product from them, buying cheap (but cosmetically good) copies, and returning the copy (saying it's the original) for a refund. Testing every return isn't something most companies do so it had become a major issue by the time they'd worked out what was happening. No reason why the same cosmetically convincing product couldn't screw up FBA co-mingling.