I bought them all and ditched them all. Passport America being the worst. If you are a pre-planned destination camper it might work. But they have SO many 'exceptions' it's ludicrous for the traveling RV'ing.
Yup you might get half off a day or a free day but you might have to stay 5 days 'during the week' in December or on a special day and space in time and only if the sun and moon are in a certain position at the same time to get half off the price for one day! :R