I honestly don't think education is the point here. _Dogs_ don't shit where they eat. Pet rats can be persuaded to poop in their cages and not on your couch. There's some kind of pressure happening here that the researchers failed to notice. Maybe leaving the village is unsafe - girls can't walk 50m downstream to a designated toilet because they'll be attacked and raped along the way. Maybe there are tigers. Maybe a tragedy of the commons has occurred where no one is maintaining the designated toilet so it turns into a disgusting pile of feces that reeks from kilmeters away. Why would anyone want to defecate there? The river probably feels cleaner, even if they know better.

My rats were litter trained actually. It took literally 1 day. During free-roaming time, I would just open the cage and put a ladder up to the bottom floor of the cage. They'd return home when they had to poop or pee.

However, pet rats might not be a good example here. This might be anecdata, but my girls would eat, shit, and sleep in the litter box. I had to buy grated ferret litter boxes to keep one from getting sick. She got E.Coli from sleeping in the litter box, and it presented as a URI. Talking with other rat owners, this wasn't uncommon behavior either.

Out of sight, out of mind.

externalities are different, no?

are they?