Even though I always have an (too cheap) annual pass, I don't object to paying money to the NPS and donate every year to the NPCA.
That said, the parking at Mt Rushmore is NOT the NPS but is a private company, Xanterra Resorts. I have no idea who they paid off to get the NPS to contract that out, but I highly object to paying a private company to park at a NPS monument. As far as I can remember, this is the only place I have had to pay to park at a National Park. That being said, this is all academic to me. I went 20 years ago, spent my 20 minutes there, left wondering what the point was, and don't plan on returning.
As for Devils Tower, the 'normal route' called Durance is pretty straight forward 5.7 crack climb, and is fun as long as you like a lot of crack and don't mind crowds.