As a company seeking to maximize profit, why would you fix this problem? It seems optimal to say "it's out of our control" -- you get to overcharge customers, and you have a reasonable explanation if a lawsuit comes.

I would be curious to see how often it's the other way around, e.g. they undercharge a customer.

I prefer to think that people (including those who run corporations at the level of -- you know -- price tags) are broadly more incompetent than they are malicious, dishonest, replete scumbags who would sooner stab a person in the back and take their wallet than give them the time of day.

It is possible that I am wrong about this.