[198d]

I think you're slightly off here. As I understand it, what these states are trying to do is consider Amazon's independent affiliates a physical presence for Amazon in that state. What that means is that Amazon then becomes responsible for collecting sales tax on items purchased by residents of that state; how they found their way to Amazon and made their purchase isn't relevant. In your example, no sales tax would need to be collected because you're a resident of Oregon and, presumably, Amazon does not have a physical presence there.

[DanLivesHere]

This is true, but what the states are trying to do is patent nonsense.

True: "[W]hat these states are trying to do is consider Amazon's independent affiliates a physical presence for Amazon in that state."

Also true: "[H]ow [a customer] found their way to Amazon and made their purchase isn't relevant."

The problem: The two statements are directly at odds with each other.