I like to play my badges like a piano, it's quite a task to find a whole song that only uses those notes, once you do "Joy to the world" there is not much left. I actually cleaned them earlier today. But I don't do it much. I usually just don't think to do it. But when I see them dirty I can't resist the urge to make them sparkle. It's usually when I go on the trainer card page to check my funds and my time played that I would do it.