I think the park could have gone a long way in easing frustration about this by doing a few simple common sense things like:
Having an annual pass available for people who use the backcountry a lot like many locals do.
Making backcountry camping free for kids
Obviously things like that are kind of common sense and sad that they didn't use much of that. I was hiking down the Long Hungry Ridge trail yesterday and very near the top I ran into a couple backpacking with their 4 young kids up to Gregorys Bald. The adults were worn out but the small kids saw us coming down the trail and were excitedly asking us "Whats it like up there?". I couldn't help but think about how this fee would affect folks like that.