Occasionally, I am assigned a piece that I just don't enjoy, I appreciate the composer and the piece for what it is, but if it doesn't appeal to me, it doesn't appeal to me.
That being said, cases of that are few and far between (at least cases where I COMPELTELY don't identify with a piece, there are various levels that one can have that feeling).
As far as for the kid mentioned, some people just don't identify with music, they don't love it. You can't really blame them, in my opinion, just as you can't blame someone who doesn't identify with philosophy, or sports, or sculpture, etc. Some people simply don't enjoy music, no matter how naturally suited they are to play. And in my opinion, that's just how those people are, they are in no way better for it, but they are certainly not worse because of it, either.
The thing that REALLY gets me is someone who claims to love music for its own sake, and is a teacher, professional musician, or other, and at the same time completely disregards entire composers and even entire periods as rubbish (hell, even Glen Gould hated practically all the romantics)