In Irish law, busking is considered vagrancy - you can be arrested for it. It's risky asking people for money in public. So it's not like it's a high-art job. And people who do it as a high-art job make very little money.
“I don't give you editorial control. I want to meet you. I want to interview everybody who's ever known you. I want to see your correspondence. I want to see your bank statements. But you will have no control over what I write. That's why I really believe in the unauthorized biography.”