You don't create anything by doing sports, but it is among the most popular and healthy hobbies. You don't create anything by playing chess. Is chess not a hobby?

And if you want to look at it that way, I can say you are leaving a collection of stamps, you are preserving little snippets of history and culture from around the world and through the years. In my case, I might be leaving sick replays of me beating SMW2 World 1 in record time, for other's to watch in awe as I do over other speedrunners' work.