Grandmaster: “Know his customers?” He may or may not, but you definitely don’t. It isn’t a kiruv shiur where he has to worry about frightening people off. In fact I’d be very surprised if less than 90% of the people there have smicha. As an aside, about half of them do wear hats. He could insure that the baal tfilla wears a hat without any trouble at all, but he doesn’t.
tbt: Really? Any proof of that at all?