For details on any of these clubs, click on their logo and you'll go to their website.
I can't say I've tried all camping clubs, but I'm familiar with all of these except FMCA. I get the impression that FMCA mostly provides "comradery", with large rallies, etc. I'll fill that part in when I have time to check out FMCA. If you've got knowledge or opinions on FMCA, email me at rjHoffman@Yahoo.com and I'll put the info online here.
But, as for the rest, here's the story. I provide details below, but the bottom line is that (my opinion):
1) "Camp-for-a-dollar" clubs like Coast to Coast and Thousand Trails charge a rather large buy-in fee, but provide a top-notch selection of private member parks (usually) across the country if you can afford the fees and are willing to take the chance on changing rules costing you additional dollars. I wouldn't recommend them for those interested in frugal camping.
2) "Discount"clubs like Escapees, Good Sam, and Passport America are cheap to join and offer you a discount at almost every public park in the country. If you're going to use campgrounds (as opposed to trying free or almost-free camping), this is probably the best way to go.
3) I've been a member of all of these except FMCA and Thousand Trails. I've been to a couple of Thousand Trails sales pitches and they sound very similar to Coast-to-Coast.
The one I'd recommend most highly is Passport America. You pay $44 per year, camp at 1000+ parks at half-price (usually $6-$7 per night), and get a membership discount for every new member you bring in. With that in mind, if you join, please mention you were sent by me -- member number R-0193449 ... thanks.
First, the "camp-for-a-dollar" clubs. There are a number of clubs like Thousand Trails and Coast to Coast -- you "buy-in" to a member park, usually for several thousand dollars, then you can camp in any of their many other member parks for some small fee or sometimes free. The buy-in fee can vary anywhere from $50 to $10,000+, and there are used memberships available, but most people pay $4000-$6000 and buy a new membership. I call them "camp-for-a-dollar" because that's what got me into Coast to Coast in 1987. It was my understanding when I joined that I pay the rather large buy-in, but then can camp forever for $1 per night in over 500 parks across the USA and Canada. I later was reminded that I also had to pay $200 or so annual maintenance fee, but that was still ok with me as long as I used the camps at least 20 times a year. Then, about 1993, the fee went to $4 per night -- still acceptable, although not as attractive as originally. Then, about 1998, the campground I had joined left Coast to Coast -- meaning I could either join another park, change from Coast to Coast to whatever club the park decided to join up with (RMI, AOR, or whatever), or try to sell my used membership. Then I moved out of Alabama, so no longer had easy access to my home park, Mountain Lakes. You want a one-owner membership for $2400 obo? ... email me at rjHoffman@Yahoo.com.
Secondly, the "discount" clubs. Good Sam costs something like $12 per year and you get a 10% discount at almost every campground in the country. Escapees costs about $50 per year and you generally get about 15% discount at many campgrounds and other related businesses, like RV stores. You also get a bunch of hugs whenever you stay at one of their camps. They also have options to dry-camp free at most of their campgrounds if you're self-contained and determined to not pay to stay. Passport America cost $44 per year and you camp at any campground that joins up for 1/2 what everyone else is paying.
By going to their sites using the pictures above, you can get an idea of where and how many their campgrounds are. I used Passport and Escapees for 3 months simply getting the member park names off the internet because my bulky mail couldn't catch up with me for that long ... lol.