A lot of religious cults will have their cult leaders practice hypnosis on their followers but at the same time tell their followers not to practice hypnosis

If their followers knew how hypnosis was practiced then they might be able to figure out more easily that the cult leader is manipulating them

In some cases the cult leader might not know that they are practicing hypnosis, they might call what they are doing something else but their actions may resemble hypnosis without them knowing it