Barbells are too balanced to develop certain types of strength. Much like you dont practice bench pressing when you want to develop strong grappling. You would grab a bag or a person and do lifts, squats, kneel, etc to develop assisting muscles besides the major muscles worked in normal weight training routines.i have found mytraining has always made me stronger that my friend who is a gym rat. He is 40 pound heavier than i am and can bench, deadlift, and squat more than I, but he is weak in motion. Weak in grappling, and weak in endurance work. So, that is why some folks do not use the "sterile" gym scene for functional strength training.