I dunno, man. a scale that runs XPSP3 maintained in a retail environment by underpaid, overworked manual laborers and has to interface with coupons, credit cards, cash, checks and EBT is gonna be a bad time just about any way you implement it. Until grocery stores start fielding in-store IT departments those stupid scanners are gonna suck.
The one I interact with is running Red Hat, they could and hopefully did arrange to administer it remotely. I say it wouldn't be that bad so long as there were actual lanes open too because then you can choose your badness; standing in line or dealing with the kiosk. If you just have a couple of things and aren't doing anything unusual like using a backpack, the kiosk might well be better than standing in line. Well, unless it's running XPSP3, which is just irresponsible for a device processing credit cards.