What about the other side of your hypothetical ending? If the shooter had NOT carried a gun, he may have serious injuries from the dogs that were charging him; one of which, as noted in the article, had a HISTORY of aggressive, dangerous behavior. My carrying a gun whilst hiking does not endanger you in the least; unless you attempt to threaten my life or that of my hiking partners. From my side of it, my carrying a gun in close proximity to you provides YOU with an added measure of security, as I would come to your aid if you were in danger. However, if you don't want such help that's fine; I'll leave you to your fate.
Justin, my point about money flowing into the coffers of anti-gun organizations was that these "chicken little" scenarios like the ones you brought up and the hyped "facts" are what AGS, Brady Campaign, et al. use to justify their efforts and appeal to donors. Without exploiting fear, they have no power to incite their patrons.
You are right. There is a chance the shooter would have been injured. I do not mean to minimize that. We have ways of dealing with that. The dogs would have been put down. The owner likely arested and at a minimum a civil suit would have been filed. Does this make up for serious injury to the shooter? I do not know and it is not for me to say. I for one know if given the choice of potentially being mauled or taking 3 rounds to the chest, I'd take the mauling.
As to your carrying a gun adding to my security? I believe you when you say you would come to my aid. I think that is the mark of a good person. However, I feel being in the proximity of you and your gun, no matter how well trained and level headed you are, reduces my security.
And yes the anti-gun lobby do use scare tactics. However this is totally valid. Guns do scare people. They should.