As a hard rule no sane parent would drive if I don't feel safe to (and that includes their ability to concentrate) because they'd be risking their children's li

As a hard rule no sane parent would drive if I don't feel safe to (and that includes their ability to concentrate) because they'd be risking their children's lives too. So we're not talking about people who are "endangering other people's lives just to get somewhere a bit faster". The point about kids is just an illustration of a distraction you might not be able to control and which might be timed badly. It could also be a dog in the car which barks at the wrong moment or countless other things. It's also a little optimistic to assume that it's as easy as "pulling over until they stop" in the cases where kids are generally being loud. There are as many examples of why that might not be practical as there are occasions when it's good advice. From experience I can tell you that no parent wants to drive while kids are screaming in the back and will readily pull over if that's likely to help. Sometimes though, it's not safe to do so or pulling over wouldn't make any difference to their behaviour (eg when they're hungry and there is no food in the car). But no decent person would ever want to put their family nor other pedestrians at risk so I can assure you it's really not the case of drivers endangering other people's lives out of a selfish desire just to get somewhere a bit faster.