[scelerat]

Playing some music and having appreciative people feed you and give you bus money simply shouldn't be the sort of thing a Work Visa regulates. This guy was a student traveling around the US, meeting people and writing about it. This is education, not work, and he had a student visa.

He just got a different education than he was expecting.

[megablast]

You are right, but the problem is where do you draw the line? And once you have a small intention of working and getting some reward, there is always a chance you might be doing other paid gigs that they could not find.

The simple fact is, if they have and reason to suspect you might be doing something a little wrong, they will deny your entry. Every country can and will do this. This is not an innocent until proven guilty option, this is ANY suspicious activity. You don't have a right to enter any country except your own.