Due to the Canadian influence in the Francophone improv scene, on improv match you see team wearing Ice-hockey jersey, referee with the black-white stripped jersey, and the public would thrown slipper at them. Making it a fun and interactive show.
But is it something universal (On matches with competing team, not on improv show who don’t have referee) or something limited to the Francophone scene ?
This comment reminded me, I have met some people who played in a French/German improv league (LIBER). They’re based in Berlin and perform in both French and German. I’m not sure how they incorporate both languages, but I believe it’s just a free-for-all, speak what you want, answer in whatever type situation.