Why Would Major League Baseball Prohibit the Trading of Draft Picks?

My friend Jimmy Golen, writing for the Associated Press, tackles that puzzling question.
As another friend, the economist Richard Thaler, says in the piece:

I cannot think of any good reason why MLB would have such a rule, unless it is worried that the teams with the highest picks are not capable of making good decisions…it has to help the teams with the top picks to have the option of trading them for additional picks.