At an all-you-can-buffet lunch, the incentives are clear: go back again and again, refill your plate and guzzle away. You would eat less if each new plate came with another price tag. Add to that a lack of self control and you get overconsumption and a desperate desire for a nap in the afternoon.
A CEO has a salaried employee. The employee gets paid much the same however much work he does. So, the CEO asks him to sit on this committee or investigate that new market or run recruiting etc. etc. Add to that moral suasion so it is a duty to work hard for the firm and you get overwork and a desperate desire to avoid the CEO. There will be many task forces and layers of bureaucracy as the cost of each initiative is so small. Better to pay for performance and internalize some of the costs of each extra foray into administration and work.