Something I learned 60 years ago BEFORE Walmart...
Small towns often had two of everything. Mom and Pop stores, two drug stores, two lumber yards, ect. The purpose was to show there was no monopoly in anything in town.
BUT, there were under the table hand shakes between the parties not to undercut each other on prices and keep the prices high. The local City Fathers also had a hand in it, keeping out more competition.
A few years back I was in California and noticed the difference between a local Walmart prices and a local grocery store prices on laundry detergent. The local grocery store price was DOUBLE the Walmart price.
You made a good point in comment #76. The competition presented by Walmart was a good thing in many areas. We do need to see new competition again, though. Walmart management has become involved in social activism for the left.