I think this is especially prevalent in schools. You'll see things like this even for things that aren't related to computers. When I was a kid, drugs in your locker were your drugs, even though breaking into the lockers was trivial and stashing drugs in other people's lockers was the way business was done.

I wouldn't have told the school of a theft I witnessed even if I knew there were cameras recording the entire thing. You're guilty unless you can prove someone else was more guilty and they're not really concerned about the truth of the matter so they're not trying to help you.