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Some Walmart employees say customers are getting hostile at self-checkout — and they blame anti-theft tech
(www.businessinsider.com)
This is a most excellent place for technology news and articles.
That has to be a location specific thing, because I've gone to dozens of different Krogers and I've never had that issue with the self checkouts. The worst that happens to me is the scales will get twitchy sometimes and think I doubled up on something, and won't let me continue scanning till an employee resets it. But even that's a pretty rare occurrence.
They've just recently replaced all their self checkout stations with new ones that do that, so maybe the ones near you are still the old ones.
They actually just installed a bunch of new stations in the Kroger closest to me, so I'm reasonably certain they aren't old. The ones they installed don't do what you're talking about though.