As a pass-time, sports are great. A bunch of friends getting together for a crack at the ball. But trading the fun for a trophy, a title, and some BIIIIIG time bragging rights, and then the game changes. It's not about having your best game anymore, now it's about being the best. It is glory by win, or shame and acceptance by loss. There are more than enough life lessons that teach the acceptance of losing and the benefits of hard work.
So when a young child is playing a sport it teaches a life lesson everyone needs to know. First the competitiveness of the sports allows the child to realize oh I have to work my hardest in order to be the best. By working hard they will also better them selves in other subjects including school