I did not know this was a thing until I came across this watching a few podcasts. Then more and more and more I realized this management industry was quite big.
And it makes sense, the performers are performers and not really business oriented for the most part. So its a vacuum that was waiting to be filled.
Then again, is it really any different from managers for actors, musicians, artists and other "normal" industries? I remember my father who was an artist had a few gallery owners who managed his sales, showings, personal commissions and other artist activities.
Now that I think about it decades later, its remarkably like pimping. Hahaha. No wonder dad had a love/have relationship with those people.