The moral argument against gun ownership is beaten over the skulls of a population with almost unrelenting force; that a gun's primary function "is" to "kill people", when in reality a gun's function is to enable a person to propel a bullet at terrifying speed using its mechanisms. The bullet in the chamber arguably does the "killing" where as the gun itself merely provides the environment and force to give the bullet its highest effectiveness, therefore increasing the probability of the bullet to harm, injure or kill. Even this is debatable, since it is impossible to prove any gun (and the bullet within) is aimed at a human target 100% of the time.
The argument bears similarity to the statement that a Hi-Fi Stereo's function is "to play music" when it does no such thing. A stereo merely provides a mechanism through which recorded media may be played back to a listener. To press further; during sex, a man cannot "give" his partner an orgasm, yet can only stimulate her (or him, as the case may be) until she (or he) reaches that desired state. Semantically, "give" implies the transfer of material or energy; last I checked, the passing of ejaculate, mucous or saliva through a membrane has never caused instantaneous orgasm alone. But I digress.
By leaving out details such as these, we tend to overgeneralize and think irrationally. The object and its adjacency to certain actions does not cause it to have the identity we ascribe it. Oversimplification and judgment, which our society craves in a modern world that dares not probe and ponder, tends to lash out at the shadows and bogeymen crafted in their own imaginations. Since we do not resolutely "live" in an imaginary world, why should we be content to speak its juvenile language?