If it is "normal" wear, it's at least inconsistent.
My previous picture is of the ascent out of the tunnel following the loop, into the banked turn. Such a small and specific area of wear down to bare metal seems odd to me, but I'm no expert.
The same can be seen on the first part of the
(correction) drop into the pit from the zero-g roll too, and also on the first part of the loop (you can see if you look down from the queueline bridge just before entering the station.
I'm sure the main wheels should be in full contact with the rail at this point, so I don't see why it'd be so patchy like this, unless there was an issue with the paint itself:
It looks to me like the paint loss is also wider than the track of the wheel too.
That said, I admit I know next to nothing about paint.