They don't bore that easily if they still went to see the habs even though they sucked and they still go to impact games even though you could fall asleep and wake up 50 minutes later and still be in a 0-0 score.
I think it's all about culture. Kids play hockey, and it's engraved in the culture here from childhood. For soccer, all you need is a rock and dirt and you can play a pickup soccer game which they do all over the world and when immigrants come here they just go to the park and kick around a ball. There isn't that much baseball here. I like the sport, and I've played softball, so for me it's interesting. But MLB has like 81 home games, that's a lot of games to make sure you have 20k+ at.