SJAA is largely concerned with observational astronomy. But one can derive immense pleasure without ever looking through a telescope. But one can observe thousands of objects with little more math than counting on one's fingers. So the range is broad. Many other interests and hobbies tie into astronomy including but not limited to photography, optics, mechanics,stamp-collecting, history, navigation, timekeeping, calendars.
Astronomy is the meeting-place of all the arts and sciences.
And your local astronomical association is the meeting-place of a wonderfully diverse group of people.