When I checked for discounted joining fees, what I found was that AAA charged more ($10-$15) for your first year's membership and they sometimes have offerings where you don't pay that extra amount. Actually, the way they market it is that years 2+ get a "discount". Apparently, the first year they charge more because they are setting up a new account. I did end up getting one of the offerings in the mail to waive the first year set up charge. I was also told that I could cancel at any time and get the unused portion of my annual fee back (minus the services I had used...I assume this means things like a tow, not a room discount).
Also, when I made the room reservation (thru CRO), I gave them my sister's AAA number because I had not become a member yet, and CRO told me that when I checked in I would have to show MY member card (and the confirmation said the same thing). When I checked in, the CM was confirming the ressie rate and info with me and I said, oh, you need to see my AAA card and I started rooting around....the CM said no, I don't need to see it, I couldn't change the rate now if I wanted to, and I never did have to show her my card or give her my number.