I can think of one easy reason from a micro-economics perspective. A firm has "organizational rents" from being more productive as an organization than the indi

I can think of one easy reason from a micro-economics perspective. A firm has "organizational rents" from being more productive as an organization than the individuals would be in aggregate on their own. This begs the question of how to divide them. The answer is usually along the lines of having a hell of a lot of political maneuvering to assign as much of the extra value to yourself as possible - salary, prestige, power, and favors.