No offense, but there's a difference between constructive criticism/polite discussion and mean spirited attacks/provocative hyperbole. People saying things like "waking up in a cold sweat" over this or claiming OCD (which isn't really funny if you genuinely know someone with it) or "you weren't planning on using it in the first place" are all missing the point. Yeah, I'm sure the poster bought this expensive computer just for show. I don't know where that guy uses his laptop where he expects it to be easily scratched but he should stop. I tend to take care of my things. I don't think I even have a single scratch on my alu Powerbook from 2005, certainly nothing that appears the way it does in these pictures. Not sure how you could've missed it, it's small but it's there.
I find the bit about 'show' to be petty. People buy Macs because they work well and also look great. It's entirely conceivable that someone would treasure the design aesthetic of their computer as much as how well it works. For something you use day in and day out, on the sofa and in bed, a device you work on as well as play on, and share your thoughts and attention with (as I'm doing now online), it's no wonder that such an intimate device would conjure a feeling of wanting to take good care of it. Not to mention something this expensive and well-designed and you open it totally new only to find it blemished without even touching it. Kinda sucks.
To the poster: For me, if someone is bothered by something that shouldn't be there and they paid a lot of money for it, they should be entitled to satisfaction. Who cares how little it is? After all, that's subjective. It's their purchase, their money. And any subjective opinion can be said without being a jerk. There actually seem to be people who have responded who think it's minor and not worth taking back but have not resorted to being one. That's how you should really do it. Ignore the haters, unless they have something actually constructive and non-mean to say.
By the way, I also thought the first reply with "I couldn't see why you couldn't decide this yourself" was hilarious.
People post all sorts of questions on this forum, whether you like them or not, it's why a forum exists.