Apple has Tim Cook. In terms of investors evaluation of his ability to generate profits - let's say apple is going to do $400B in sales, and you think Tim's approach over time will yield a 3% improved margin. Is he then worth $12B/year? CEO's have enormous influence on a companies direction.
Investors will automate MANY MANY things before they automotive the CEO's job.
Let's be a bit serious. What would make Walmart investors more nervous:
1) Being asked to pay all workers $35/hr, or
2) paying the CEO an extra $1M/year?
1.6M employees * 40K+ pay increase = $64 Billion per YEAR. Let's get a grip on what