The value of Amazon is not JUST prices, it’s the full set of services that come with Amazon (admission: I pay for Amazon Prime), AND the fact that Amazon stands as storefront for a plethora of other, smaller specialty vendors.
Wally World wants to offer a selection of its’ general stock online. Amazon pretty much sells any and all legal merchandise on the planet. . .
Their online selection goes far beyond their store stock to even include other vendors.