I believe polo is the “sport of kings” but the reason is similar.
That’s what I always heard.
This is from wiki.answers.com, for what it’s worth:
The Sport of Kings often confused as horse racing but it is in fact the game of POLO. .associatedcontent.com/article/43201/the_sport_of_kings_is_not_horse_racing.html?cat=14
Read more: http://wiki.answers.com/Q/What_is_called_the_sport_of_kings#ixzz1f9Kr78SP