Some of these parents were mean to take it so far, just to attention whore for TV. It would have been one thing to quickly say that they ate their candy to see the child's immediate reaction, but to drag it on and insist they did it was wrong. You can also tell that generally the parents with the kindest voices have the more easygoing children.
The parents with the most brash personalities who like to rub it in the most tend to have the children who react the most negatively.
Something tells me that the children who have the most loving relationships with their parents here shrug losing candy off the easiest, while the children with the bossy and the most teasing mean parents need the candy more at an emotional level to compensate for their less than emotionally supportive parents.