I agree with you. When I shoot I shoot for long periods of time. JV and Varsity games, etc. The grip gives it a little extra weight that helps to dampen the hand holding and when switching from vertical to horizontal the Grip release and multi-selector helps tremendously.
For sports and wild life it also increases the FPS for some. Certainly for sports I will take all I can get.
But that is all personal preference.
Just like firearm long distance shooting and competitive long range shooting, the heavier the weapon system (to a degree)the more stable the platform.