Why Baseball Managers Wear Uniforms Too

On the rare occasions (like during the World Series) when I watch baseball, I've frequently wondered why the middle-aged managers wear uniforms just like their players.  That sure doesn't happen in NFL football or in the NBA.  And it looks a little silly to me. Why is that done in Major League Baseball? 

THIS article on CNN this morning answers that question.  It's a tradition with long historical roots, apparently. "[I]n the earliest years of the game in the 19th century, 'The person who was called the manager of a team was the business manager -- he was the person who made sure that the receipts were paid and that the train schedules were met. He didn't make any decisions about what went on during a game. The person who did that was called the captain. He did what a manager does today, but he also played. So at first, the person we would today call a manager wore a uniform because he was a participant in the game.'"