For me, it is about removing an attack vector crazy people might use. We live in a time where people can seek revenge for the pettiest things. In thepastt, I had gotten into an argument on reddit over something harmless and they doxxed me and sent a warning to my house. I deleted everything and overhauled my privacy.
Its meant to save you a step. Before at whole foods you had to get out your phone, open the amazon app, scan your prime QR code, then get a card and pay. This just does all that with an enrolled palm.
I still don’t trust it. I laughed at it when I saw it and even the clerk admitted it was dumb.