It's a lot of psychology, Lazs.
Guns are made to kill, or at least inflict damage on a target of some kind. Cars and power tools only do so when mishandled.
Guns are objects of recreation for a majority of owners--the biggest exceptions being cops and soldiers, and it has been thoroughly pumped into our heads that even for those two professions, the use of a gun should be considered last resort. They are not directly necessary to the continuation of our economy the way that cars and power tools are.
Finally, after years and decades of public service announcements, billboards, movies and after-school specials, the image of a loaded gun in the hands of a curious 7 year old has been burned into our collective mind. A gun in the home, in the minds of many, is a tragedy waiting to happen. Couple that with the fact that we do not depend on them as much as we do on saws and drills and SUVs, and you get demonization.
Not saying I agree with all this, I can just see how these factors lead to general attitudes about firearms--especially in the minds of mothers.