This is a very interesting topic and I would like to add my personal view about sumo.
Obviously, sumo is a sport. Sumo wrestlers are athletes who pratice and train to win in their sport.
Ozumo is a professional sport, attracts sponsors, rikishis make fortunes, media... just like any other professional sport.
HOWEVER, and this is where most foreigners are mistaken, ozumo is MORE than a sport.
It is easy to compare rikishis to any other profressional athletes but people need to understand that there is a difference which is hard to explain as a foreigner.
Asashoryu's behaviour wasn't that terrible for me. He was an amazing athlete, good in any sport (have anybody seen him playing basketball??) and he acted as a professional athlete, which was not enough according to the sumo kyokai criteriae.
The shinto ritual, the outfit, the chonmage, the referee... is obviously the mark of the "more-than-a-sport" sport.
I am a fan of the sport, the way they train and eat and get conditionned for their fight, and the religion and ritual part just add something more to ozumo which make it a fascinating sport.
