Whether it was "Camptown Races" or "Ave Maria", the bands were equally adept at playing the music and hamming it up for photographers. They seemed more adept at hamming it up for the photographers who sat in the chairs being served by the café's waiters, while those who were not paying for drinks would get an equally hilarious take -- without missing a beat, the musicians would grimace in a nearly gargoyle-ish frown as the person approached with their camera.
Here you can see that the violin player on the right is fingering the strings and hamming it up, while the player on the left bows the strings for him and gives him a noogie.