You still seem quite eager to judge while not really understanding the culture. The point in Scandinavia is that parents should be the ones primarily deciding how their children are raised and fed. Of particular concern is feeding junk food and candy to children who are not your own.

We have foreigners here who will just give candy to kids without asking parents. That may be cool where you are from but that is straight out rude here.

You also seem to not have picked up on an important point I have kept emphasising which is that dinner time is considered and important family event. Parents want their children home for dinner, not eating at random places.

About phones. No, I don't know the phone number of the parents of every random kid that drops by. Why would I? Neither did my parents when I had friends on visit. It seems like you don't get that these are unplanned visits not playdates arranged between parents.

Leaving a kid to play with some toys or games is not rude. Usually this happens through mutual agreement. You may suggest that they should go home for dinner but perhaps they have eaten or will take longer time before they have their dinner. They may express a wish to stay.

In my family, we do actually ask on occassion if kids want to eat with us, but most kids don't want to because it simply isn't the culture here. Their parents expect them home or they think it is awkward to attend a family dinner or don't want to impose.

I have waited for friends myself when I was a kid. Never found it rude or insulting. In fact I would have felt uncomfortable if they had asked me to join their dinner. Just because something is rude in your culture doesn't mean it is rude in mine. I am sure there are plenty of things you find normal which would be rude over here.