I think many rely on used gun sales. At the LGS that I frequent, I once saw the owner purchase a little Beretta .22 or .25 for $75 and when I saw it on the shelf a few weeks later, the price on the tag read $250. Whether he actually got that price or haggled it down a bit, it's still not a bad deal on the part of the LGS.
I have a mild interest in guns. Actually, I think the clinical term is "obsession," but that makes me sound like some kind of gun-nut. Which is fair, since I am.
Wastin' away my future children's inheritance one box of ammo, range fee, and bottle of Hoppe's #9 at a time.