I think the vast majority of street performers will disagree vehemently if you call them beggars; personally, I wouldn’t really include the windshield washers in the beggar category, although I’d be more inclined to do so than in the case of street performers. The fact that the latter perform a service in return (and frequently not even a bad one, many street performers are talented and have a solid musical education) distinguishes them quite clearly from beggars, IMHO, who are only appealing to people’s commiseration.