Music editors, from I can tell, don't make much money. I don't know anyone that does this for a living. Certainly if I added up the reproduction costs of music sources, I don't even think I'm breaking even. That's ok, I do this for the love of the art of music. But I value what I do, and want to be paid something for my efforts. So when my editor found one of his editions was online for free, my heart sunk. You can read more about this here.