Parents find justification in their jobs (or simply because they have no interest in the children they have given birth to), and leave the children to the system.
And the system needs to turn children into young addicts, with as little education as possible, to be cheap labor, consumers in that system. Even if they consume unhealthy food, and because of illness they spend all their savings and die before reaching their pension, the system wins.

I remember when I was a kid, the two of us, the fastest in the whole class, on a long break between classes, we ran to the nearby railway, where plum trees grew.
We climbed into the treetops, filled our pockets with green pickled fruits and took them to school. We ate them so green, sour unwashed and none of us ever had any stomach problems.
We probably burned all the bacteria in the body with constant physical activity 🙂 (I'm probably in my fifties today, fitter than some young men in their twenties or thirties).