I developed many weird and useless skills as a child, like, will juggling while walking around on a bowling ball ever be useful? No, no it will not, and neither will knife throwing.
Still, the difference between "I am going to put this knife in the block right above the other knife" from say, 5 feet and 10 feet is very noticeable, while at 20 feet it's more a matter of "I want to put this knife in the block, and I'm going to try to see if it ends up right above the other knife" really, and out at 30 or more feet it's "I want to put this knife in the block" without much specification on where it lands. Using a bow or crossbow gives quite a bit more accuracy with practice and a stable target out to a good deal further, though I've only used a bow a handful of times I did carry a slingshot basically non-stop, and given consistent ammo shapes I could plunk a specific bottle sized target from a hundred feet pretty reliably.
I've never taken out a bird or squirrel, but have tried.
Hitting someone in the hand or shoulder or head at some distance if they aren't moving is one thing, if they're trying not to be hit then you're doing well to hit them anywhere, much less "I'm going to shoot their left ear off without accidentally sticking a bolt through their head" type trick shots.