We can say all we please that we want great customer service, but we vote with our wallets, and our wallets say "Save $5 per trip to interact with the trained monkeys."
Thus, we have Walmart.
This is very much a cultural problem that stems from treating service workers as subhuman and undeserving of a decent wage.
And the price difference is hardly as high as $5 per trip. Even places with really high minimum wages don't get that bad. It's more like a few extra cents, barely noticeable. Where the savings on payroll at the bottom are going is usually payroll further up the chain.
Some stores have much better customer service than others, like Whole Foods and Costco (just to cover both sides of the pricing models), and they seem to be doing all right.