Americans’ shopping habits have changed somewhat over the last few decades, but that’s not necessarily because of e-commerce. Two economists at the University of Chicago argue that the rise of warehouse clubs is what has really changed Americans’ shopping habits and the retailscape.

Maybe this will change after consumers have had a few more years of buying everything they possibly can from Amazon Prime, but here’s something to consider: online shopping represented only about 4% of consumer spending in 2012, while about 8% of all spending was in warehouse clubs.

While nationwide data only goes up to 2013, Americans spent $348 billion on e-commerce and catalog purchases in 2013, and $420 billion at warehouse clubs during the same year. That data, from the Census Bureau, goes back to 1992, and shows that mail-order and online purchases increased about 990% during that period, while warehouse club sales increased 1,500%.

Much of the catalog industry died out or moved online during that period, yet warehouse clubs, which include BJ’s, Costco, and Sam’s Club, just kept growing. While most retailers are trying to sell online and integrate their Web and in-store inventories in massive “multichannel” efforts, other companies aren’t really trying to imitate warehouse clubs.

However, the e-commerce site Jet.com had a splashy, well-funded debut earlier this year, and it is trying to imitate warehouse clubs: the company has stated that it wants to sell merchandise without making a profit, and instead make money from the $50/year membership fee that customers will eventually have to pay.

A case that Costco and other warehouse clubs have transformed retail more than Amazon [Washington Post]

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