Japanese soccer fans are well known for cleaning stadiums after matches. Scenes of them sweeping stadiums and picking up trash after a match first drew public attention in France in 1998 — Japan's first appearance in the World Cup. Since then, the tradition has continued and it's certain to continue in June, when Japan plays in the United States and Mexico. People from other countries are often surprised by this behavior.

There are cultural reasons behind this habit, starting in childhood. In many Japanese elementary schools, students are responsible for cleaning their classrooms and school areas. Koichi Nakano, who teaches politics and history at Sophia University, explains that fans at global events behave the same way they learned to as schoolchildren. There is even a Japanese phrase for this: "Tatsu tori ato wo nigosazu." The literal translation is: "A bird leaves nothing behind." In English: "Return it the way you found it."

William Kelly, a professor of anthropology at Yale University and a specialist on Japan, said the tradition is linked to soccer more than other sports. He wrote in an email that the J-League was trying to distinguish itself from baseball by emphasizing teams' strong ties to their local communities and commitment, and that soccer fans felt, and feel, more a part of the club and its stadium.