Just think about other sports like football, hockey, basketball. If they cut away to a couple of talking heads while the games were going on, they would destroy their audience. In golf broadcasting, there are so many cameras around the course, there is something interesting to show all the time.
Let them do their commentary, as much of it is very interesting, but why telecast their two or three of THEM when there is action on the course!
An example, Harry Caray, calling the Cardinals and later the cubs games, would comment, tell stories or jokes, but the camera's stayed on the game.