I would say it is normal wear, because...it's rubber, you know? It's gonna wear. Instead of swapping bands and wasting natural resources on trashing a fully functional band, just take an eraser to it and rub off the rest of that surface coating. Your new band is going to start looking exactly the same eventually, wether it's within days or weeks or months. Because, it's rubber. Rubber wears.Yeah, the oil/rubber on rubber markings are definitely normal wear, but not so much the peeling.
Next batch of bands Apple makes might not have any surface coat at all, as it's just costing them money when panicked people run back to have their bands replaced.