If you return it, it's rather likely you could get one with bigger defects.
The new 15" BTO MBP I ordered in 2011, had a rough oval patch on the lid, about 5" in diameter that was very rough to the touch, and visibly coarse. I've never seen anything like it.
Yet Apple was very good about replacing it. The only drawback was I had to wait until they received it, and credited my account. Once that was done it was a matter of starting all over, placing another BTO order and waiting.
Finally after just over nine weeks I had my new MBP with just a few marks like yours. That one I kept.
Thanks. This is the kind of response that helps me get over this petty issue. I know there are much worse issues that happen everyday with new devices. My girlfriend went through 4 2011 MBA's for assorted different issues before finding one that she was content with. First one had a chunk of aluminum taken out of the bezel. Second had some weird bubbles under the screen. Third one had dents on the bottom.
I know I need to get over myself, I'm just going through the stages of grief I guess. This is the most expensive and best computer and I've ever owned so I guess I placed my expectations too high.