[jkaplowitz]

Cherry-picked? That suggests they went out of their way to arbitrarily pick something just because it had the ideal set of judges or laws. It's simpler than that - it's where they're headquartered. Pretty much every contract ever drafted picks the home jurisdiction of the drafting party as the chosen venue (if not arbitration) and chosen law, absent some specific reason to do otherwise.

Sure, Amazon is a very big player there, but by no means the only big player (e.g. MS and Boeing are also based there), and all the full procedural and substantive protections of the US and Washington judicial systems apply, aside from the right to a jury. Everything is much more restricted in arbitration.