I think they've determined that the amount they lose due to theft is less than the cost of paying the wages of a checkout person.

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If this is going to be a Christian nation that doesn't help the poor, either we have to pretend that Jesus was just as selfish as we are, or we've got to acknowledge that He commanded us to love the poor and serve the needy without condition, and then admit that we just don't want to do it.

- Stephen Colbert.