For the people of Walmart, the problem is Walmart makes a ton of its money by vacuuming up all the low/no income customers that would have been served in smaller numbers by convenience type stores. If they go upscale like Target or Trader Joes, they lose that customer base and move into competition directly with those types of stores. Same with the layout. Sure, you or I will pay more for a store laid out for actual convenience and fully staffed decently paid cashiers that will get me in and out quickly, but most of their customer base wont.

It reminds me of Mcd’s problem. They can’t go upscale because people that will pay for it already like places like Chipotle or Chick fil a more and Mcd’s is so deeply branded as the classic cheap fast food. And their current customer base is heavily weighted at lower income busy people looking for the ubiquity, price, and mentally easy process.