I'm not all that familiar with Sumo wrestling, but from what I do know, it's an intriguing ancient martial art in Japan. With that, it's highly ritualized and includes:
"... both step back into the ring, squat facing each other, clap their hands, then spread them wide (traditionally to show they have no weapons). Returning to their corners they each pick up a handful of salt which they toss onto the ring to purify it."
Would you get mad at this guy for spilling some salt on your floor? I wouldn't.