Actually, I have used the "Homer gets a gun" episode as a training aid when orientating new shooters before heading to the range. Homer is a boob and so we see many examples of poor judgment and poor handling regarding guns. In contrast,the NRA members (including Dr. Hibbert, old lady Agnus, Moe and Lenny) are portrayed as responsible citizens exercising their 2A rights.
BTW- The scene in which Lenny connects five guns (a luger, SxS, 1911, e.g.) to make one super gun; who here hasn't actually thought about doing that?