I've seen numerous bucks taken during gun season with an arrow in them (not visible from outside) from the year before. Also know many rifle hunters that got cut up from gutting their buck and hitting an arrow in them. Their bodies grow like a grissle around the arrow and they heal. I will shoot a deer if someone has blown a leg off or similar. This buck wasn't doing good a week before (per the SIL) but is acting normal as could be now. He should survive. Probably will break or chew the arrow off sometime.
I see so many bowhunters that can't hit the side of the barn on tv. If you look close the arrows aren't hardly penetrating, they're hitting them in the guts etc. and then someone off camera finishes them off for them. I can only imagine the number of similar or worse bowhunters out in the woods. I'm sure that statement can also be made about rifle hunters also but arrows (IMHO) are less humane.