People have a proclivity, when given sensible orders, to follow them. To test their obedience, you must give them insensible orders - only if they follow those will you know you have control.
Madness string 82933
Sometimes learning 'people get really upset if you do this' while not changing someone's thinking does change their behaviour. Yes, changing thinking is best, but someone staying quiet in order not to offend people is still better than them being an asshole.