That is not the full story of why Walmart Succeed, the Old School walmart (back in Sam Walton's day) was not competing on price, but on Value (Service + Price) and they successed
Walmart of today still competes on more than Price, but it is Convenience + Price. For me this is the ability to get my Oil Change Supplies, my Furnace Filters, a new pair of shoes, a belt and my Groceries all in 1 store, with 1 checkout, and I can get into that store and out of it getting everything I need for 1-2 weeks in under 30-45mins
Often times if I price shopped for every item there are places that are lower in price than Walmart, and some that are higher, but on the whole those minor fluctuations are not worth going to 5 different stores to get the "lowest price"
My sister dragged me, kicking and screaming, to one of those new Walmart Neighborhood Markets. I was shocked to learn that it didn't suck. They definitely invested in their self checkout things (unlike Kroger). I even found some foods which didn't contain HFCS. I've been back a few times.
Walmart of today still competes on more than Price, but it is Convenience + Price. For me this is the ability to get my Oil Change Supplies, my Furnace Filters, a new pair of shoes, a belt and my Groceries all in 1 store, with 1 checkout, and I can get into that store and out of it getting everything I need for 1-2 weeks in under 30-45mins
Often times if I price shopped for every item there are places that are lower in price than Walmart, and some that are higher, but on the whole those minor fluctuations are not worth going to 5 different stores to get the "lowest price"