I just turned on a medal game for the Olympics in men's handball, which I've never watched before. The referees are wearing the Adidas WC 2010 style soccer referee uniforms. And I saw the referee show a player a yellow card on a foul. Seems like an interesting game with some similarities to soccer except for the whole hands instead of feet thing.
I get it now! All those times I was doing pre-season games and those players yelled handball... OK, good.