With that many people, do you realise how easy it would be to cheat? Imagine sitting in the middle; you could pull out a bloody tablet and start watching tutorial videos and get away with it.
Yeah, but the Chinese people have very little of that going on because of their culture. In their country if you get caught it is seen as shame, not only on you, but shame on your name. And that shame reflects your parents and their parents and your children.
Although, you could just have a sign or sticker on each desk saying "cheating punished by sniper". That would work.