Public transit is a big factor. https://www.bloomberg.com/news/articles/2015-09-28/in-japan-small-children-take-the-subway-and-run-errands-alone https://www.blo

Public transit is a big factor. https://www.bloomberg.com/news/articles/2015-09-28/in-japan-small-children-take-the-subway-and-run-errands-alone https://www.bloomberg.com/news/articles/2015-09-28/in-japan-... > In Japan, small children take the subway and run errands alone, no parent in sight.