Why do they put stickers on liquids at grociers?!

Question: When you buying litters of milk or water or liquid drinks they put stickers on it (small blue or red tape stickers).

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Answers: When you buying litters of milk or water or liquid drinks they put stickers on it (small blue or red tape stickers).

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It is usually the larger items and not just the liquid items. It is usually because the bags are too small for the large object or people take them out of bags and it shows they have been paid for

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