I believe we buy on emotion, and justify it aftwards with facts and reason. We know what stirs our emotions, and we "gotta have it." While showing it off to friends, or explaining to our wives, we say things like, "It's the last of a kind," or "better get it now while we can," or "This fills the gap between the guns I have now." Actually, the same can be said for most purchases, especially impulse purchases. Kirby has made millions selling a fine vacuum cleaner, at a very high price, on the emotions associated with wanting a clean home, and a quality piece of machinery. (appeals to both women and men) Think about other major, but non-essential purchases, such as pools, spas, cars, etc. Fun in the sun, soothe your aching back, etc. Then after you bought it, you will extol those features as the reason you "needed" it.
I'm not trying to discount sales appeal, just explain why we buy what we buy.