I think you may be referring to U.S. fans, because to a vast number of baseball fans of every other team in the final six, this is akin to a hardball World Cup. Fans of Mexico, Venezuela, Japan, Puerto Rico, Cuba... even the eliminated DR, are all agog over this tournament for bragging rights.
The WBC is important in promoting baseball across the globe, and you can bet there's increased interest in the sport now in places like Italy, Great Britain and the Czech Republic.
Most of the pro guys would already be playing baseball games in Florida or Arizona anyway -- the two U.S. sites for both Spring Training and the WBC. And let's be honest, as much as Grapefruit and Cactus contests are welcomed this time of year, they're basically meaningless as far as keeping score, and even sometimes vapid to watch anonymous replacements taking their sips of big league coffee.
Competition and emotion is what really makes the WBC -- or participating and/or spectating in any sports -- fun.