If consumers purchased the codes *knowing* they were obtained illegally and may likely be revoked, then you might have an argument. But it's become routine for people to offload bundled codes for relatively cheap (yes, upwards of 50% off or more at times). I've bought them for years. There was no reason to think these particular codes were potentially bad until the Amazon scam was revealed. And many people were still selling them at the expected "legitimate" market price. (If you payed like $7 for GoW4, then you were just gambling)
That said, don't trust anyone when it comes to BST deals. Online, in-person, always minimize your chances of never seeing your money again. Don't do PP friends and family unless you've dealt with the seller/buyer personally multiples times, and even then. Try not to put yourself in a position where you have no recourse. I myself have been scammed before.