I've been wondering: why would you give a story to your child where you have to explain that "these people are dumb", "this is not something you should do", etc

I've been wondering: why would you give a story to your child where you have to explain that "these people are dumb", "this is not something you should do", etc at every page. About that subject, the song "au clair de la lune" really disturbed me when I was young. Everything seemed weird about it, combined with the fact that it stays in your head, that really made me wonder what I didn't know about this world. Turns out the song is about banging a prostitute, so now I see why this and other things that disturbed when young were indeed disturbing. I see why you would want to avoid telling a story about parents abandoning their child at an economic downturn, and instead find stories with an uplifting story. [0] https://en.wikipedia.org/wiki/Au_clair_de_la_lune https://en.wikipedia.org/wiki/Au_clair_de_la_lune