Many people, when visiting remote wilderness such as Glacier Park, Montana, fail to recognize that they are in the wilderness, sharing the forests with all of the wildlife in Glacier. It isn't a drive through zoo nor do guardrails ensure you needn't worry about safety.
Glacier is, indeed, wild terrain - yet something everyone should see in their lifetimes. As cities and asphalt take away what used to be rugged beauty in places like Colorado, Glacier National Park is a large area that is still protected from development. Because of this, wildlife you don't regularly see elsewhere consider Glacier their home.
Grizzly bear are found in very few locations anymore in the continental US. I've seen them and, when I do, it is considered a privilege and a thrill. Quite honestly, I am more afraid of humans than I am of nature. In addition, grizzlies are not hiding behind trees, hoping to pounce on humans. Bear encounters are rare, injuries from bears even moreso.
That said, taking off on a hike into Glacier puts you out in the wild, on your own. You need to carry bear spray, travel in groups, and read up on how to recognize bear signs. Park trails aren't there because they ensure safety - they are a way for you to go deep inside Glacier, to experience its beauty.
So be sure to visit Glacier National Park and all of its beauty - but be aware you are seeing nature in its purest form. Use common sense and you will have a safe, memorable vacation. If you're anything like me, its magnetism might relocate you permanently.