First, I have an article that might help you:
Various Memberships for the Weekenders and FulltimerSecond, really pay attention and think about your style of travel. I have (and love) Harvest Hosts but I almost never use it. We rarely overnight and, if we do, we'll leave after work and arrive late; outside of the business hours for the business. And, since we rarely overnight, Passport America doesn't make sense either. Usually weekly rates are better.
For us, we use the heck out of our Thousand Trails membership. Other than my yearly dues (which I pay about $625 in November), we haven't paid a nightly campground fee since January 1. In fact, we're lining up to mostly not pay anything until mid-August (we have a couple of "splurges" on places we want to go in there).