Stores may be more likely to throw in an extra of some kind rather than drop the gun price.
I have bought most of my guns, both new and used, at small local gun shops. As a result they don't usually have extra examples in there inventory, what you see is what they have.
That said, in dickering on the price I am more likely to get an extra something or two thrown into the deal than any signifficant reduction on the asking price.
I've come away from some deals with a couple of extra mags that were list price more than what I could expect the dealer to drop his asking price on the gun.
And yes, I consider an unfired, never transferred gun in the display case to be NIB.