I'm not sure if they still have it, but in the early 80s Oklahoma had a 'minimum price' law to 'protect mom-n-pops' from undercut competition.
Walmart was just moving into the state and had a hard time because they wanted to offer prices lower than the state would allow.
"a 'minimum price' law to 'protect mom-n-pops' from undercut competition."
They still do that with gasoline here in Wisconsin. Aside from the outrageous taxes we pay on a gallon of gas, they also have a "minimum markup law" that doesn't allow anyone to undercut their price per gallon and start a "gas war."
Probably a leftover from Jimmuh Carter. Worst. President. Ever.