Well, for one the net worth increase of his heirs has little to do with the company. If they are making interest on the wealth they have, that doesn't effect walmart in any way.

If we want to do a calculation, lets do it. The CEO of walmart makes 20mil a year. Lets kill him and redistribute his salary amongst the workers. Their hourly pay would rise.... less than half a penny. They would get about 9 extra dollars per year.

Whoopty do.

The reality is that CEOs are paid a lot because they are worth a lot. They have the potential to effect the salaries of workers several orders of magnitude more than by giving away their own money.

Example: The current CEO made enough extra money in 2015 to raise everyone from 9 to 10 dollars an hour base pay. That cost ~2 billion. He could do that because he was leading the company really well, even in a time of reduced growth.

His 20 million salary is absolutely worth it, even to the workers, when his decisions lead to enough money being made such that they get a dollar an hour raise... not less than half a cent.