Most fairytales and bedtime stories that used to be told to children are very very scary.
Dr. Bruno Bettelheim (one of the most famous child phsycologists of his day) actually has an entire book studying this phenomenon and points to their unquestionable effectiveness at giving over certain moral values.
And those who say that teaching such stories are “ineffective”.
Such stories used to be standard fare in teaching yes the positive was taught the “schar” but also the “oinesh” the punishment.
Nowadays many feel only the positive should be taught not the consequences at all.
Another thing nowadays is that we complain about childrens sense of entitlement, lack of reponsibility and lack of derech eretz and failure to “grow up” and machure.
Seems to me the old way of chinuch did work.