If you read some of the posts within the forum, you’ll realize that “getting a better body” is only a part of why many of us do this.
Setting and exceeding goals in the gym and for the physique can in turn be used to propel the other parts of one's life. I see it as some sort of synchronicity - one part of my life will definitely affect other parts. I exceed in my goal of, lets say, bench press, and I will of course, feel pretty swanky, self-assured, pretty damn good about myself. That feeling will carry on to other areas - I use it that way. In other words, fate does not control my life: I do. Bodybuilding enhances my strength, my self-worth. It also helps with my creativity and provides me stamina to deal with the stresses of everyday life.
And I have plenty of strength to give to "help others". Via bodybuilding. Now, bodybuilding hasn't been the only road I'm traveling on. However, it has been the "unseen guide" - it's always present in some form. It's a intrinsic part of me. Like art, for instance (I'm an artist).
It'll come down to this: there is no simple answer to your question(s). Since everyone is different and we're all in different places (in our lives).