What's your source?  I'll call BS on your statement.  Guns have been used for bear protection for centuries. Bear spray, not so long.  So of course long term statistics will show "bears shot and continued the attack" more for guns.  Because guns have been shot at bears exponentially more times than bears have been sprayed.  These women really screwed up by not having shotguns on them.  Often the sound of a shotgun, even if you don't hit the bear, is as good or better than bear spray in scaring a bear away.