Community Kid Minding
Having had some experience minding my grandchildren, I notice that it is very difficult for a single adult to mind children. The fact that you can't leave them, even briefly, is incredibly inconvenient. This is even worse with two kids. If you need to go to the shops you have to drag both kids along. It can be quite hard to control both of them. The mind boggles how a single adult could cope with 3 or more kids.
With two adults things become manageable. One can be left minding kids while the other goes to the shops or many other things. Two adults minding 10 kids works better than one minding one.
Modern life often doesn't work without a lot of effort.