It's a little unfair to playmakers since they'll rack up more secondary assists than goal scorers will, and are punished more in these per 60 primary points comparisons.
Removing them implies that all (or most) goals are created by either the goal scorer or the last person to pass them the puck. But anyone who watches hockey enough knows that's often not the case. Puck carrier carries the puck from the D-zone, through the neutral zone, backs up the D and enters the O-zone, then drops a pass to a trailing player who shoots it, goalie saves it, and someone stuffs in the rebound. The secondary assist on that play created the entire goal, but he'd be "punished" because LOL secondary assists are cheap.