I became a fan of the Missouri Valley Conference solely because Arch Madness was located in St. Louis (hence, the name). I have no rooting interest in any specific team, but I am obsessed with this conference because of that tournament.
If it moves to Kansas City, I would be devastated. Sure, I'd find a way to get there, but it wouldn't be the same. You all may not agree with me, but I think the city of St. Louis does actually embrace the MVC as much as it can. Local media coverage is solid. The Post-Dispatch pumps the hell out of Arch Madness when March rolls around and follows the league for the most part from November to March. Fox Sports Midwest plays at least one and sometimes 2-3 games in the STL area a week. People do care about this conference to some extent in St. Louis, and losing Arch Madness would be a terrible, terrible thing.
Keep it in St. Louis. It's tradition. Attendance is fine, and it rises and dips only based on the competition level within the Valley from year to year. It sold out in '06 for obvious reasons, and it took a hit two years ago for obvious reasons, too. Has nothing to do with STL not being able to hold the event.