I think he was just using a very, very extreme example to show you that anything can be listed as "service" if you frame it in a certain way, so a line has to be drawn somewhere. Your situation is obviously much, much closer to this line than someone who goes on a vacation and proclaims that they "brought people together." I think what you did is wonderful, and it was probably a great asset to the community. However, great asset to the community does not equal community service. To give an example that is closer to your situation, the difference between service and leadership/extracurricular/hobby is the difference between making meals at a soup kitchen and starting an organization in which people (yourself included) get together over a meal (that you prepare) to discuss important worldly issues. While both of these are lovely things to do and both of them impact the community in a positive way, only the first is service. Merely giving of your time does not equal volunteer service. If you start or maintain an organization that allows you to participate in your hobbies, this is not volunteerism, no matter how good it was for the community.
Despite all of that, this sounds like a really great activity that you have invested a lot of your time into. You can certainly talk about the skills you gained and how hard you worked to make this basketball league happen. Stating that it is not volunteer service in no way diminishes what a good activity it is. Mark it down as a leadership opportunity/extracurricular and then let the adcoms know what a great activity it was.
