My experience with passport america is that is may not be worth it. Stopped at 5 last year. Three had decided not to honor the PA rate due to the solar eclipse. One that was full offered an overflow space for $110 per night. Yes, I understand that many advertise no PA rate at certain times of there season, this time was not listed. We spent the night at Walmart in the next large town. I've had the problem that there, many times, isn't a PA campground near me when I want to stop. I did stay at 2 PAs last year, both good places, one was exceptionally nice to stay at, the other was nice but right next to an interstate with plenty of traffic. Still, worked for us.
We don't mind staying at Walmarts if they allow, but they are sometimes noisy. There are many businesses that welcome you if you are considerate. We stayed at a Burger King in Minnesota that had a dump station. Woke the next morning with a pig hauler parked next to us, luckily the wind was blowing away from us and not at the store, as the odor was intense and we wouldn't have been able to eat our sausage biscuit.