I always like to keep an eye on the players inside the penalty box because a lot of time goals are scored when the other players caught off guard by one of the players coming out of the box, got a cross-ice pass from his teammate, raced down the ice and put the puck in the net. It is specially great when it is a two-man advantage penalty.
One more reason I like goalies as they never had to serve penalty for their misconduct. (Ice Hockey Official Rule 407 stated that a goalkeeper shall not be sent to the penalty bench for an offense, but instead the penalties shall be served by another member of his team.) Like the time when a penalty was called against Chris Osgood for tripping David Perron (a penalty was also call against Perron for diving), but the penalty was served by Jiri Hudler, instead of Osgood. Goalies just have to work harder when his team tries kill the 2-minute penalty.