Others that began as e-tailers-only are beginning to move into physical retailing, albeit in a lighter weight pop-up store format.

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RetailWire asked its BrainTrust panel of retailing experts what they thought of the potential of the Walmart Express format as well as its impact on the competitive landscape.

FORBES: Walmart Testing Express C-Store Concept

Clearly online retailing requires a lot less retail property space compared to traditional brick-and-mortar format employed by big retail chains like Wal-Mart, Best Buy, Target and Costco.

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