Side business or not, it's still a business, so they should be expected to stand by their work. Every customer is different, and if those creases really get to you, I say you have every right to demand your money back if you feel it's warranted.
They should have
1) Told you about the creases if they were there already. This effects the value of any item, especially NOS..
2) Packaged the material properly. There's no point is selling something as NOS (or Brand New) when it gets to you looking like it's been used.