That's okay. None of the dealer's seemed to mind my conscientious approach. Especially when I wanted to pull a car out of the box and the plastic so I could examine both sides. It meant no fingerprints or smudges for the eventual buyer.
I guess I am pretty Monk-ish about trains. I keep my own trains as flawless as possible - dusting and cleaning them regularly when they are on the track, and keeping all others stored in a dust free environment.
I have no intention of ever selling them. But if I kick the bucket, and my son or daughter isn't interested in the hobby, my wife can get top dollar for them.