Uncle Steve began to say much of what I was about to say. Many of us busk for serrious, not just grins. Your welcome as anyone else, but if you are in earshot of another busker, find another place and if you are louder, go farther. Smile at anyone puting ANY money in your case, even insulting amounts - like the Italian tourest who video taped me playing the pipes in a broiling subway station for some 15 minutes, then droped ten cents in the case, smile because if some jerk complaines about you, we all get run off. Play like your life depends on it, as if there is a lot of bad music out there, neighbors complain, and we all get run off, not to say there is not a place for new musicians on the street, many folks learn to play better by the incentive of the more cash that comes in when you do things well, but try very hard to do your best.
Good luck
Stay well
Larry