The math for those large cooperations is a bit more complex than that. CEO compensation is often mostly stock options, which has a value for tax purposes, but is not a value that can be easily reinvested into the company. The actual cash salary portion of the compensation package is usually peanuts compared to company revenue.

They're basically trading the CEO partial ownership of the company in exchange for running it, and I'm not sure how you would go about forcing any kind of change on that, without unintentionally breaking things for smaller companies and startups.