Walmart's Sam's Club has bold food court change to take on Costco

Picture, if you would, the average grocery store anywhere in the U.S.

If you wandered into one this weekend and asked your fellow shoppers whether there was something else they'd rather be doing, the overwhelming answer would probably be yes. 

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They might tell you their weekly trip to the supermarket is a slog. They'd rather be fishing, watching television, gardening, and for the people who really hate shopping -- maybe even getting a root canal. 

That, however, is certainly not the case at a Costco  (COST)  or Walmart's  (WMT)  Sam's Club. 

If you were to wander into one of those this weekend, most shoppers would probably tell you there's nowhere else in the world they'd rather be. 

And they would mean it. 

Costco and Sam's Club both have loyal followings. Their members are fierce devotees who spend multiple hours each month looking through the aisles looking for the best deals on their staple items -- like organic produce and high quality meat -- and for more novel items. 

Warehouse grocers have a unique business model

Part of the reason customers go wild for warehouse grocers is because they are distinctly different from your run of the mill grocery store. 

While traditional supermarkets offer lots of variety; the average grocery store carries between 15,000 to 60,000 items, or SKUs. 

But many of these items are either loss leaders or offer very little value to the bottom line. 

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Consider, for example, how expensive it is to stock over 10 different kinds of pasta sauce, crackers, or chips -- all of which perish within a short period of time. 

Warehouse grocers, on the other hand, carry far less product selection.

But what these retailers lack in variety they make up for in price. 

Both Sam's Club and Costco buy their inventory in bulk, allowing them to negotiate prices down and pass these discounts on to consumers. 

Plus, a lot of these goods are typically sold under private labels, which customers often hail as some of the finest quality for the price. 

Sam's Club makes another competitive move

When it comes to market share, though, Costco tends to be more popular than Sam's Club. 

Costco accounts for over 60% of the warehouse market, whereas Sam's Club has just under a third. 

And Costco dominates in the size game, too. It has over 600 stores across the U.S. 

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Sam's Club, however, is expanding at a rapid clip of about 30 new stores per year.

And now, Sam's Club is planning another competitive move to take on its biggest rival. 

The warehouse club announced it will extend its food court hours to keep up with consumer demand. The new hours will be: 

• Monday through Saturday: 10 a.m. to 8 p.m.
• Sunday: 10 a.m. to 6 p.m.

Sam's Club is also making its pizza available for curbside pickup. Many customers report its pizza is even better than Costco's, which has its own food court cult following for its low prices and high quality.