That Amazon lets anyone seemingly be anyone, even major brands, as sellers, and lets blatant frauds continue for long periods of time, is a serious problem. This isn't the buyer's fault whatsoever.
Good they got a refund, but it's nice that they shine a light on it.
This is the key, at least from my perspective. If I go to Amazon (or any other online vendor) and an item is listed as being by "International Brand X", I expect that the item is, in fact, being sold by "International Brand X".
Amazon doesn't list the seller separate from the brand. The way the page is lad out, it is clearly meant to indicate the manufacturer is the seller.[0]
I, too, am guilty of assuming when I buy a product it is actually the product and not a different product.
The fault lies with Amazon for knowingly and intentionally adhering minimally to the law because it is more profitable to do so than to launch an effective crackdown against counterfeiters. If they forced sellers to get verification from the companies whose products they purported to be selling, or proactively banned sellers who are obviously hawking counterfeits (before a journalist shines a spotlight on them), they'd lose profit. We need laws that require these things, and levy fines large enough to be a clear deterrent against those who break them.
Indeed, their behavior is illegal even under current law. They intentionally obfuscate the seller, and prevent revealing a seller as a counterfeiter on product pages. This is knowing abetting of counterfeiting. Amazon is almost certainly the largest and most flagrant abetter of counterfeiting in the United States.
At the very least they could add a "verified/unverified" badge to store names and give verified status to manufacturer outlets.