Well, here is my 0.02: I think that today, in urban societies, people has been conditioned NOT to use a knife (or a gun, or flashligth), because they had been taught to DEPEND on others (the State?, the Police?). Judging by the opinions presented, there are people who are used to fix many (most) thing by themselves (the forum members), and there are people who don't. Besides, there is the the perception that many people have of a knife (any knife): a weapon. If one stop to think, western society tends to the avoidance of "dangerous object": cans that don't need a can opener, electric pencil sharpeners, electric razors, and many other instances (not to mention firearms).
Men is becoing less and less self-reliant. Every time I use my folding knife to sharpen a pencil for the nurses or secretaries in my hospital, the look at me like if I just had sprouted a horn in my forehead.
So maybe that's the reason (or one of them), why so many people don't use a knife: they have been portrayed as dangerous objects, used only by weirdos or delinquents (and like them, many others objects, that were nothing but tools).