I'm not going to define it as a sport since it probably doesn't fit the textbook definition of one.
However, like I stated in my previous post, at the end of the day, it has about as much point as taking part in a rugby game, or a game of tennis, or whatever sport you play.
By this I mean:
In the grand scheme of things, if tomorrow everyone stopped playing:
Chess
Rugby
Tennis
Bowls
American Football
Would it have a major impact on the world? (Now I'm not talking about all the economic related things such as advertising etc. just the actual game itself.)
At the end of the day, sports are just games that have become more entrenched in society than another...