Yep, the hiker ends up with a crushed bag of bear drool embedded food. The bear still gets a taste and is taught that ursacks and humans equal tasty stuff. I guess it's kind of a fun thing from a materials science point of view on indestructible cloth technology, but it sure seems pointless to me.
I guess it's useful against raccoons and other small vermin, who I assume wouldn't be able to crush your food into drooly pulp. Maybe they should have named it the Raccsack?