Knowing about the existence of crime in a general sense is not legally or functionally the same as knowing about or being directly involved with a specific instance of crime.
> I mean, if I had repeated instances of someone else performing illegal activities in my basement, I can't continually, or even once, claim that I had no idea.
Amazon does not claim that they are unaware of counterfeit products on their platform. They do explicitly say they are aware of fraudulent products on their platform, and they have blogs on their website that talk about this.
> Just because it's hidden behind several layers of software abstraction does not mean that Amazon doesn't have explicit knowledge.
They are generally aware that marketplace sellers list fraudulent products. They are not specifically aware that any particular new listing is fraudulent until after the fact.
> These products even physically sit in their own warehouses.
Sometimes they do, but not all of the time. However, putting the item in a warehouse does nothing to authenticate it.