Galahad,
I saw that on a special on the History Channel a few years ago. The Eskimo being interviewed said that the ammo was light and cheap, the gun was reliable, and they could carry a lot of ammo on long trips.
BTW: your chances of encountering a Grizzly are a little less than your chances of being struck be lightning.
According to the national safety council, bees kill about 100 times more people than bears every year.