I dont think the issue warrants any form of outright replacement, they may repair it under warranty out of good faith as its not confirmed from day 1 as being a manufacture defect.
The reason the hinge is black plastic is for better reception for the AirPort card and Bluetooth module.
Before they were having issues under the aluminum casing of the previous unibody models.
generally all they have to do to get the hinge cover solid, is tighten the screws holding the display in place
UPDATES!
Just came back from Apple store, Verdict is. Initially the Genuis told me exactly what i expected. Cosmetic part blahblahblah, they are mass produced parts, and sometimes they are like that.
So i keep myself claim, and replied. Oh yea? But the person that ive spoken with over the phone said Apple will repair that particular part for me Free of charge.
He then look at his mbp to check some notes. ( shouldn't he be doing that prior my existence ? ) Anyhow, he checked and said ok yes we will replace that part for you, went in and check for parts. As expected , part is not in stock. Have to order it in and have me take my mbp back and wait for their calls.
Now , He did mention a few times saying that even tho they are replacing that with a brand new genuine part. Because its been mass produced, we cannot guarantee that after repair itll look 100% perfect. So im like are you saying this for " just in case" and im not likely to have a repaired mbp that id be upset about again. He's like , yea we just don't guarantee that itll look BRAND NEW with no damage.
i.e. it might get scratched or dents while tech is putting my laptop back together.
That brought to my question.
-Should i fix it now?
-Should i take the risk of opening the laptop by Apple tech and risking a perfect working laptop that hasn't been open at all.
-Should i get over it and be grateful of my mbp as its not actually noticeable and lucky its not anything else.
-Blame myself on not noticing the small dents within 14 days.
-USE IT and buy a new one next year.
-Sell it ( reluctant to do so )
-Buy a 2011 new one and give this to my gf lol.
Thats about it guys sorry for much non sense.
Generally speaking , how the Genius go in regards of service.
Here is what i think, if they "think" you know what your talking about, and being relatively polite. They will try to help you.
If you do not know much about what your whinging about, and being arrogant, they can care less. They did mention at the end , wanted customers to have positive feedback.