I believe that Virginia does have a discounted state parks permit. My recollection is that the annual permit is 50% off for seniors, and gets you free admission and discounted camping fees. I don't have one, however,because I don't camp in the state parks here often enough to justify the $100+ price of the discounted annual permit.
But I did spring for the $10 Federal lifetime pass (deal is for those over age 62) that gets me free admission (for the whole carful of folks) and 50% discount in camping fees. Paid for that the first time I used it. I bought it in Death Valley, and didn't have to spring for the $15 admission fee. It's been great since then at Grand Canyon south and north, Bryce, Zion, Sherando Lake, Skyline Drive, and more. I look forward to using it several times a season for years to come.