So why was this movie made?
My Theory

Brad Pitt is secretly envious of baseball managers, they don't have to care of 10 adopted children.
 
They say star athletes make bad coaches. This man proves the rule, Billy Beane turned down a scholarship to Stanford to play professional baseball. He failed miserably, yet he retains his romantic attachment to this game.  

"You sir, have the the boorish manners of a Yaley."

Peter Brand, an Ivy Leaguer, who has never really played the game, all he has is a degree in economics. A poster of Plato hangs in his bedroom. He believes in a detached, dispassionate, scientific approach to team building; which is challanging; baseball is like time, the variables are ever changing.