$1:
The men were given notice that there was a bear in the area, but no one told them a bear had been seen in the campground and had attacked tents, he said.
Sounds like Parks Canada did its job just fine.
The problem is that too many tourists think bears are more like Winnie the Pooh than top-of-the-food-chain predators. When I go camping, I take bear warnings very seriously, and even if there isn't a bear sighting, I still take every precauion possible.