I was actually just thinking about coupons and how this would change that landscape. Physical coupons would be pretty useless I could imagine, everything would have to shift to digital, unless you could scan them on your way out, which would then just defeat the purpose of "just walking out". I think my mailman would appreciate it regardless, due to the large amount of unwanted coupons that get put in my mail almost daily.
Seems like you'd want screens to help people with stuff, so they could double for scanning coupons. The problem with checkouts isn't the scanning, it's that they have to create a physical chokepoint.
