Are there schools that don't do this, gifted or otherwise? It was pretty common in my experience. Teachers might even give some kind of small reward to kids who got 100% on a test, the best essays were regularly read aloud (and credit given to the author), etc.

I even had an Algebra II teacher who would post the recent top test scores and their owners in a corner of the board. It was one of the few classes where I wasn't regularly on the top, either. Maybe I should have been doing some of that homework after all? Nah... close enough.

I don't see any problem with publicly acknowledging good performances. I would have a problem with publicly calling out poor ones. "Praise in public, correct in private" applies here.