Your not understanding us.....its normal. My dogs in a day groom eachother about 1/4 to 1/2 the day. I am also sure they are not doing this for 24hrs.
Please take our advise, especially since we have an animal behaviorist telling u its normal. We are not trying to be mean but you are being cruel. If your chi's are grooming themselves then it needs to be done.
Also, if they are doing it a lot maybe they have something wrong...like allergies. If what you say is ture and they are doing it ALL DAY maybe they have allergies...but i highly doubt they do this all day.
They are probably bonding...either way you punishing them is not right...its wrong and it will cause behavioral problems later. Again would u like it if you were punished for cleaning urself...just think in a day how often u spend cleaning urself in one way or another, either by washing hands, face, while in the bathroom, showering, etc.....