No one would accept a new car like that, why should you put up with it on a bike? And if it is a common fault I'd have it replaced with a different make.
If you anyone doesn't mind the odd chip and scratch they are better saving money and buying second hand. New, you want it 100%.
This was my original thought (posted as such but deleted and rethought it based on Kiriyamas thoughts...)
As always, we can have different ideas about what's OK and not. I'd be unhappy at first but then as kiriyama says, personally I'd probably forget obout it after a week.
Based on that, I'd almost certainly push for a discount, that then partly satisfies the quite rightly disappointing blemish in the finish.
In my opinion, touched up paint looks worse than the original chipped paint.
Hmmmm., that can be true too.
OPs decision ultimately comes down to the following...
Not prepared to accept whatsoever....demand a refund and as it seems a common fault, change bike to something else altogether.
Disappointed but accept in a couple weeks you'd forget all about it...push for a discount and perhaps a touch up...or get it replaced and hope the next one is perfect.
Then, this kind of thing annoys me. It's a circa £1500 bike with a known fault. As long as people keep buying them, the manufacturers are getting away with it in a sense. How many times have I heard people buying Spesh or Giant bikes for instance that complain about poor stock wheels...unless people stop buying them, the problem will never get sorted.
