Curval, it's not a matter of "needing" a gun. I see its usefullness in protecting my family and I, but that's not my main reason for owning one.
I own them because I hunt. I'm going deer hunting with my father and brother-in-law this Friday.
I own them because their fun to shoot. Why else own 20 of them, including full autos?
I own them for protection, I am a prosecutor in a state where one was almost gunned down last year.
I also own them for home defense.
But, while two of the four reasons are defense/protection reasons, I'd own them for the other two alone.
I grew up in a house where my dad collected military firearms. He owned over 100; from (at one time or another) a .50 cal HBM2, a Vickers, Owen, Bren, 1917, 1919, Lewis, BAR, M-60, MG 42, Thompson, Sten, Sterling, Mac-10, and assorted M-16's and AK 47's. One friend owned a British 25lb'er cannon and another owns a 37 PAK cannon. Why? Becuase they are damned fun to shoot. And thank God I live in a country where I can pursue this hobby.