If you don't have some sort of card + short-pin access to the scanner (or something else that's minimally interrupting), auth is an incredibly annoying thing. I mean, what's the threat vector here? Scanned butts? I think people will survive.

Everyone's supposed to have some fancy alphanumeric-with-special-characters password and sit there in front of the machine copying it in slowly from their LastPass. No, thank you.