i mean the fact that it's a known thing to seal babies magic should they discover it, means it's not unheard of, also nobody want magic babies, babies are horrible creatures, cute horrible creatures but also cruel and annoying as all hell.
Babies make messes everywhere with everything they touch or can get their hands on. So not letting them just conjure up a ball of water in the library because their 2 month old ass doesn't know that books shouldn't get wet, is just good for all involved. Plus, most babies wouldn't need to use magic before 5 anyways.
At that point, you're not talking different customs, but different natural instincts. You'd literally have no one having the urge to hit someone without wanting to grab an implement to do so.
I think the point is made more in relation to fighting monsters or armored opponents. It's not very human to only bring your fists to a no-rules life-or-death fight (except in some fantasies xD). How many wars have been fought with just fists? How many hunts of big animals? That's the comparison
The point is that saying it's not "human" is using the wrong modifier. It's very human to fight with your fists. It's just not conventional or cultured to do so against armoured opponents, but then you're already not talking about what's "human" to do.