Bob you should indeed be pissed off - the lousy way that performing music professionals are often treated across this country is appalling. That was one of the main reasons I started this thread. But remember you cannot let your anger sit there and stew, because it does nothing. You have to turn it into positive action. So to start, I'm going answer some specific questions you asked about the American Federation of Musicians union:
if I or my band were in a union could we possibly get jobs anywhere?
Bands or groups don't become union members - that's done individually. You are any number of your bandmates could decide to join. I am not aware of any music venue that has said right out that union musicians "need not apply" so you could play about any gig that is available to you. However, that leads to your next question -
Are you allowed to play "non-union" gigs if you get offered any?
I think the terminology you are looking for there is, does the gig pay "union scale" which means the lowest acceptable fee per hour to member musicians. Scale can vary from time to time so it's good to check with your local on that. But once you know what it is, the union expects that you will not play for anything contracted under that amount. If you do, you could lose your membership because, as you can imagine, by playing sub-scale performances you would be totally undercutting what the union is all about which is fair pay and treatment of musicians.
What are the union dues?
Annually - $125 Quarterly - $34.00 Federation Initiation Fee (one-time): $65.00
Would it be worth it for a part-time band to join a union?
That would depend on a couple of things: One, how much you like being treated basically like an indentured house slave as a musician, and two, how often you play out. You do not have to be a "full time" musician to join the AFM. The AFM is an organization that is split into smaller branches called "Locals". I hope you don't mind but I took the liberty of doing a Google Earth search and found the AFM local nearest to you in Lexena, Kansas. It's in Kansas City MO. (Local 34-627) and here is their information -
http://www.afm.org/34-627/
Irminsul, does this union you belong to been beneficial to you in your musical endeavors?
Yes it has, in some unexpected ways. I have been an established session musician for local studios for some years now (piano, synth and celtic harp) and thanks to an AFM supplied job lead, I did one hour on a movie soundtrack - playing with the recording full orchestra - and walked out with an $1,100 check. And this is not that atypical.
This is a good place to tell you about some of the benefits of joining the AFM:
Your recorded and broadcast performances (as I illustrated above) get top dollar.
AFM members are also eligible for the AFL-CIO Union Privilege Program, which provides special loan rates, credit cards, legal services, and even pet insurance. Yeah, pet insurance.
The AFM offers an insurance plan, and get this...even a retirement pension. The AFM Employers' Pension Welfare Funds are one of the most secure plans out there. They offer normal and early retirement, death, and disability payments.
Now Bob, understand that I mostly joined out of principle. I believe that musicians should not be treated like third class citizens, and that they have a right to make a living. This crap about having to PAY club venues to play is just pure bullshit and needs to stop. But that can only happen with numbers. Enough folks who will not only refuse to play in that arrangement, but who will tell nightclub and bar owners why they won't so the word gets around and the practice stops. This is also the power of the AFM or any union for that matter - strength is in numbers.
Good luck to you and your band, you guys really deserve much better than what you are getting according to your post.