In all other sports I agree with you (I don't want to hear anything about "winning" the 1997 NFC championship), but baseball is different. Because of the history, the historical nature of the leagues, winning a pennant is a major goal in and of itself. Not the ultimate goal, but still a very significant one, and one worthy of celebrating. I guess that since they still are 2 different leagues, it would make sense (and thus why they hang a banner/pennant), but I agree that it would be dumb to celebrate "Western Conference Champions" or something like that.