Haven't the (big) supermarkets in the US adopted the whole "scan and go" thing that lots of countries in Europe have had for a long time? (maybe more than a decade at this point I think)
When I go to the supermarket, right after the entrance, I pick up a scanner, then as I pick stuff, I scan them and pack them. Then when I'm done, you scan a code, give back the scanner, take your stuff and leave. Kind of assumed this was done in the US first and then spread here, but maybe it started here? Not sure.