They are sliding barriers at the self-checkout area that open when a receipt is scanned.
This is an anti-theft device for upscale stores. The article below describes what the ghetto stores are doing.
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SAN FRANCISCO (KGO) -- Shoplifting continues to be an issue for stores across San Francisco.
Shoplifting crimes increased by 20% in San Francisco from pre-pandemic stats in 2019 to 2022, according to the state department of justice.
Now, a Walgreens in the city's Richmond District is locking its freezers with chains in response.
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Like that's going to help. Shoplifters are brazenly stealing from these stores and the employees are powerless to stop them. What's going to stop a thief from walking up to the sales staff and asking them to unlock the freezer and then helping themselves to everything in it and walking out without paying?