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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.
I would guess this wouldn't work in many countries with a more prevalent stealing culture (among which mine, France).
I don't say that out of nowhere, it shocked me when I went to Sweden and I saw people alone leaving their bags at their place while they go to the bathroom / getting their orders, or just leaving their bike unattached - even for five minutes I would guess it would be quickly stolen in France.