It's good to have a hobby"

I ask myself what defines the difference between a professional and a hobbyist. I'm not going to use the term amateur. The dictionary defines an amateur as "one lacking in experience and competence in an art or science".  I believe anyone now days with a camera or phone can take an interesting photograph. Now the dictionary defines a professional as "one participating for gain or livelihood in an activity or field of endeavor often engaged in by amateurs".  So it becomes pretty clear it is about the money.