Let's see if I've got this straight-curling is now an established Winter Olympics sport.
Curling is semi-popular in Canada, a country with few entertainment options, and one about as populous as California. It does have its adherents in Scotland, its "country" of origin. Basically, though, curling is not a sport with a big world-wide fan base.
Baseball is popular in the US, Canada, Mexico, much of the Caribbean (the Spanish speaking part), Japan, S Korea, Taiwan, and Venezuela; and has an increasing presence in Australia, Brazil, and much of Europe. But baseball is no longer a Summer Olympics sport. Why?
UPDATE: I posted this on Facebook and got a snotty response from a Scottish guy, who asked me why the World Series only includes North American teams. Well, a curling world series might have somewhat limited appeal. But you could have teams from Canada and Scotland. Woo-hoo.