Actually they aren't charging you to walk in a National Forest. If you drive there and park at a number of WMNF trailheads, there is a parking fee. No one is forcing you to go there so you have the choice to pay, stay home, or walk there. The parking fee just isn't that much.RickB-"Charging a citizen to walk in a National Forest is wrong."
If you're over 62, get the lifetime America the Beautiful – National Parks and Federal Recreational Lands Pass – Senior Pass. - Cost $10.