It also doesn't hurt that Walmart effectively hit its moonshot. It murdered a million small businesses / local stores / mom & pops and in the process did make things a lot cheaper for many people.
They optimized the supply chain of the traditional retail model to its limit (and then over it in legally questionable ways) and changed how people buy a lot of things forever.
That being said, Walmart wasn't really innovating in doing it. It just did what everyone already knew worked but did it with less empathy and more scale. Its much the same way the current Amazon store site for regular things isn't innovative - they took something other people were doing and mixed in some scale and evil and came out on top in that regard.
To Amazons benefit, it was/is innovative in web services, book sales, warehousing, etc. But as a retail store? Until recent years they just took the Walmart model gone digital and ran with it, and somewhere along the way took the Ebay model and pasted it in as well.
It might also be to Amazons benefit that it was founded within months of the first ecommerce websites rather than some thousands of years after the first store chain or a hundred after the first integrated supply chain.
"The Arkansas-based company reported strong growth online, with e-commerce sales soaring 50 percent in the fiscal third quarter, a year after it acquired Jet.com. That's a slower pace than in the prior period when digital sales were up 60 percent."
