I see many cases of what I would consider abuse at tournaments all the time. Kids are sent out to run around hot gyms for an hour or two completely bundled up in sweats, coats, hats, etc. to lose a couple of pounds in a very short period of time. This type of activity has been proven to be very dangerous to the particpants heart and can cause long-term damage in a very short period of time.
Kids go out and wrestle with severe sprains, head injuries, etc. because their parents or coaches tell them they have to go on (you hear it all the time: Be a man, suck it up, etc.). All of this is abuse in one form or another since it places a child (and anyone under 16 is still definitely a child) in a physically or emotional dangerous situation.
My son had a mild head injury during his first match yesterday. Once seen by the medical officials there was no question in my wife and my minds what the right thing to do was. We took him home. His future health and success is too important to jeopardize for a match or two, no matter how big the tournament.