One of the great international soccer traditions is supporters wearing their team scarves. There are millions of pictures that show these scarves in action.
You can read about the history of this tradition here, where they have this quote:
Just think about how much you treasure your club or national team’s jersey; some fans treasure their scarves even more. It is a symbol of their undying love for soccer and their team, a link to the other fans and part of their identity.
An in this article, another great quote:
A soccer scarf is now commonplace at any game–internationals; women’s and lower-division pros; collegiate, high school, and youth clubs.