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The Self-Checkout Nightmare May Finally Be Ending
(gizmodo.com)
This is a most excellent place for technology news and articles.
This must be location dependent (and time). I have multiple Walmart and grocery store chains nearby, and the worst I ever see is one Walmart may sometimes have a line at self checkout... But I usually know by how full the parking lot is.
One grocery store never has a line, one grocery store does occasionally at rush hour (both the same chain, about 5 miles apart).