For better or worse, I've been an Orioles fan for about 20 years now, and there is one tradition that I always loved: During the Star-Spangled Banner, everyone would scream "O" during the "O, say does that star-spangled banner yet wave." If the singer was unaware of the tradition, it could really throw them off. But, you have to know your audience. Now, every time I hear the song I quietly let out a little "O", but never more than that unless I'm in the DC area.
Well, apparently this has annoyed many DC fans. There are still many Orioles fans in the DC area and they should show their pride (what's left of it) at all sporting events, despite what a few old curmudgeons have to say.