Different workouts are for different things.
Bodybuilders work out with an objective to do two things: get huge, and get ripped. Professional athletes, such as NFL football players, work out with an objective to do two things: get stronger, and get faster. Using this as an example, you can clearly see how much workouts can differ from each other. A professional bodybuilder probably has arms two or three times bigger than an average NFL player. But, the bodybuilder could also be slow as a snail. Reggie Bush can run a 40-yd dash in around 4.33 seconds, something that no bodybuilder is capable of, and if they are, they're in the wrong sport.
The point is, to be a professional bodybuilder, you have to train very specifically for the sport. It doesn't matter if you can squat 20 pounds or you can squat 2000 pounds. All that matters, with bodybuilding, is that you look like you can.
Bodybuilding = Physical appearance
Sports = Physical performance