Hi,
CAA card may give you a 10% discount at some commercial campgrounds. You do have to be bold and ask for the discount.
Passport America may be the only card that I would consider. But then, I mostly boondock.
http://www.passportamerica.com/I search for coupons for restaurant meals--but I sure don't pay "extra" for such discounts.
I contribute to the following website as often as I can:
https://freecampsites.net/Don't forget that, on a rolling average, you may only stay in USA about 120 days per calendar year, and that if you stay longer than 31 days a closer connections to Canada form needs to be sent to the US revenue service.