> A grainy image of your palm

I really doubt getting a reasonably good image of my hand is tough for Amazon. But they don't really need my palm at all; most of the point of that was probably that it'd be much freakier to normies if the self-checkout just said "hi Bob!" when you got close via facial recognition.

> Then tying that to your identity is very hard and takes manhours…

That seems deeply unlikely. I'm probably on 50 different cameras at a Whole Foods, some of which I'd never notice, and at some point I have to check out, which ties all that footage to a credit card and my Prime account if I don't want to pay the non-deal prices for everything.