Let's face it, all chat serves no real purpose. So if a player has been banned for trash talk a certain amount of times, why not take away their ability to talk to the other team?
Seems like an easy solution to keep players from ending up on the tribunal multiple times for trash talking the enemy.
© 2013 Riot Games, Inc. All rights reserved. Riot Games, League of Legends and PvP.net are trademarks, services marks, or registered trademarks of Riot Games, Inc.