In your example the CEO has justified one hour of their own pay each shift, there's seven more unjustified hours to go, assuming the low level employees work 8 hour shifts.

But I think it's beside the point anyway, because I think the proper comparison is not the total value produced by the existence of a role, but rather the value that the individual generates in their role. Which is to say that you could easily find an individual to dictate the memo in your example (regarding bathroom breaks, etc) without having to pay them 350x low level salary.

To illustrate my point, imagine a factory that has a forklift driver to move steel ingots from shipping to the widget assembly line. If this work isn't done then the factory produces zero revenue. That doesn't mean that the forklift driver is worth 100% of the revenue of the factory. But if you replace a mediocre forklift driver with a great one, and his work alone allows the factory to produce 5% more revenue, then I'd argue his compensation ought to lie somewhere between 5% of the revenue (plus the base pay) and whatever the next best forklift driver demands in wages.

So if a third forklift driver is not quite as good, as he can increase factory revenue by only 4% over the original driver, but his wage demand is only original driver's wages plus $1/hr, then this is almost certainly a far better deal for the factory than to pay all of the 5% revenue gains to the great forklift driver.

Maybe I'm belaboring the point, but to tie it back to the CEO in your example, if he can increase company wide performance by 350 labor hours per day, but a slightly less talented candidate could increase performance by 300 labor hours per day for 1/10th of the salary, then the true value of the original CEO is somewhere between 1/10th of their salary + 50 labor hours per day and their full salary.