Here's how they do it --
They steal it from one store in a chain, then return it to other stores in the chain, claiming they lost the receipt. Chances are good they have friends/relatives that will help in that process. Much more profitable than simply selling stuff to people they know (ie, a "fence").
Many retailers won't chase shoplifters, much less detain them. Not only are there well-publicized stories where someone dies, or a person is wrongfully detained and hurt in the process, but quite frankly, there is "commonly" a racial aspect to this crime.
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