You should have said "OK then, since it's new I would like a refund."
I had my own BB issues the other day. There's a guy that works there that's really good at trade-ins, some more people that are pretty good and then...one guy who is a moron and acts like he couldn't care less. Guess who I got? So I gave him my Dark Souls II disk. Not trading in the metal case or extra stuff, but that's never been a problem in the past. He punches on the computer a bit and finally goes "I don't think we can take this because the only one I have listed is the Black Armor edition." Long story short, I spent the next 10-15 mins either trying to explain to him that it's the SAME GAME, the "Black Armor" was just a metal case preorder thing and waiting for him to supposedly talk to a manager. He never even acted like he heard what I was saying, let alone understood it, just kept parroting back the same line to me. Argh!