In Svalbard, the arctic archipelago administrated by Norway, anyone leaving Longyearbyen is required to carry a rifle for their own safey. For grizzly bears, Wikivoyage recommends that Bear repellent spray (a very strong pepper spray/mace) is considerably safer than carrying a rifle. This answers says the same thing.
From Wikimedia commons
I'm no hunter and I would hate killing any large mammal (or even small non-mammals). Is the statement about the safety of sprays vs. rifles accurate for all kind of bears? Don't bears run so fast that by the time they're within the range of sprays, they're already so close that it's more or less too late to defend oneself?
(Note: I've only hiked in Europe, and nowhere I've been are any dangerous animals apart from humans)