A more important reason is that the bands will intuitively trust someone they think is a peer and who speaks fondly of the same formative rock and roll experiences.
From the beginning I knew intuitively that if nothing else music was safe and that nobody could tell me anything about it. Music didn't need a middleman whereas all the other things in school needed some kind of explanation.
There is beauty when something works and it works intuitively.
The director's job is full of all sorts of annoyances and details - like how many cars are on the street. Ugh. I don't want it. I like my gig. And I feel that for the next 30 years or so I can keep learning more about it.