Quote Originally Posted by viperwasp View Post
Plot hole Ninjutsu?
Maybe it's because the villages have to respect the tradition of the chuunin exam by not killing participants? I mean if you're going to kill participants in every chuunin exam, there's no point in having one because all the villages will just be assassinating all the children from every village.

It's a very sensitive political matter as well. If we all had a G8 summit and at one of these summits, and a French journalist gets killed, the countries might go to war or boycott future chuunin exams with each other over that and that goes against the intent of having them in the first place:

Quote Originally Posted by Naruto Wikia
In the past, each village held their own chūnin exam. After the Third Ninja World War, allied ninja villages agreed to hold the exams together at the selected village that would host the exam. This was done to improve relations between the villages and prevent war between them.
http://naruto.wikia.com/wiki/Ch%C5%ABnin_Exams

I guess you could ask why Konoha just doesn't send an ANBU assassination squad after Kabuto when the chuunin exams end. I could probably reason that he's a master spy, so he's able to hide himself quite well.