My wife and I just had a long discussion about parents we know who spend a lot of effort perfecting things that don't really matter while they ignore issues that actually have survival implications for their children. This is like militantly keeping your kid from high fructose corn syrup while leaving them in the care of your ex-con boyfriend.
What are the possible explanations for this? One is parental friction, that the dangerous practice in question is a point of contention between the parents. Parent A thinks it's important to keep the kid away from poison, but Parent B thinks it's no big deal (or thinks it's equally important that the kid have access to poison), so Parent A decides instead to parent the crap out of time spent playing video games.
Another explanation is parental ignorance. The parents don't know poison is dangerous, or they can't understand a hierarchy of threats and treat all hazards as equally worthy of their attention. I've read before about the lag in learning urban sanitation standards by new city residents in the early 20th century. Basically they bring with them their hillbilly understanding of cleanliness (or slovenliness, as it were), and in the close quarters of urban life, they create disease. Evidently it takes several generations to learn that trash cans need lids. Maybe the same thing is happening with these parents and their misplaced priorities. It takes time to see and respond to existential threats.
Maybe it's parental helplessness. Instead of direct inter-parent conflict, it's just the world in general that's keeping the parents from addressing the bigger problems. So my kid has a problem with malnourishment, but since solving that is difficult, I'll just keep them from eating any chocolate that isn't fair-trade certified.
All of these possible solutions leave me unsatisfied. If the parent just completely ignored parenting issues, it would be easier to understand; he's either not up to snuff as a parent or doesn't care enough to try. But parents who try hard, just at the wrong things, can't be easily explained.
Of course, they'd say I'm guilty of the same problems. "You keep your kid from high-quality education," they'd sniff. But even if we grant that public schools offer a higher-quality education than my children receive at home (which I don't concede), that's an issue of my maximizing on a different metric. I'm not trying to maximize their socialization or their scores on standardized tests. These conscientiously-negligent parents say they are maximizing their children's health, but then pick low-impact ways to accomplish it while ignoring high-impact ways.
NB: The "math" label has become the "science" label has now become the "health" label.