Of course, brick-and-mortar retailers are getting into the game, too.

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This was, of course, when brick-and-mortar shops still outsold their online brethren.

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Brick-and-mortar retailers are fighting back again such e-commerce trends, of course.

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Of course, startup Netledger had the luxury of building from scratch -- not always an option for large brick-and-mortar companies.

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