I'd like to make one comment here...
I own and operate a business in my small town and county in rural Ohio. 'Everybody knows everybody', as folks often say. After many years of conducting business in the public eye (meaning we're a visible presence here) people still don't know who we are and what we do. They ask what we do, and then say "huh!...never heard of you 'til today". What's my point?
Any group or organization needs to constantly pound their name and ideals into the public's eye. If membership is needed, people must know YOUR NAME, and they must know exactly WHAT YOU OFFER. Having a vague idea or semblance of understanding is not close to enough. Being misidentified, misunderstood or worse...invisible...causes people to walk away. Again: Tell people who you are and CLEARLY define what you stand for, and what you offer for joining.
I say 'offer', because the majority of people don't spend money in order to join a work effort. If you want their membership and money, give them something real and visible in return. The fact is, most people want to pay money and get something for it. If they want to work for the organization later...fine. Expecting them to do work is unrealistic at best. Any organization exists only because of its members, and it must continually strive to attract and please them.