When I hit the road full time I bought ALL the CG club memberships.
I found they all had waaay too many restrictions to get a discount and many of the CG's listed when called said they don't give the discounts anymore. Or you had to stay the 3rd Tuesday of the month to get a discount etc. etc. etc. Threw them all in the trash.
Just travel and when you find a CG that you stop for the night that you really like ask for the monthly rate. All CG's whether they list it or not have a monthly rate and it IS a way cheaper way to RV. :C