I'm a Cards fan too. The supposed Cards-Royals rivalry is because they are in the same state, it doesn't mean they are rivals. The fans in KC are the ones making a big deal out of it. Kansas city, though not a traditional rival, and definitely not on par with the Cubs, is definitely not one-sided, and it's not just about the same state. There's also the World Series history, and the Royals' one shining moment was also something that had played a part in what was one of the longest stretches of no titles for the Cardinals. Obviously that changed in 2006. Add in the fact that there was one specific play that both sides could argue about (even though it didn't determine the series), and there was definitely a back and forth between the fan bases. If this was all one-sided, then you wouldn't have Cardinals fans driving across the state in droves for the series every year.. I disagree. It may not be ALL one sided but it is certainly HEAVILY one sided. The Royals have had ONE season in the last 15 over .500 Hard to have a rivalry when the best zinger a Royal fan can throw happened 25 years ago As to the "droves" of fans driving across the state, how many of those fans do you suppose live west of St Louis? A good number I would suppose. Add in the fact that since the Royals suck, it is usually easy to score some GOOD seats Heck, its not uncommon to see a good sized contingent of Cards fans in MIL when the Cards play there. NO, I would definitely say it is more along the lines of the MIL fans thinking they have a rivalry with the Cubs and not that my circle of friends is a representative sample but not one of them considers the Royals a rival.