I agree with you 99% ... the other 1% of me doubts the state government will use the extra revenue to do anything constructive for those pristine areas.
As with many of these things it's a matter of principle vs. practice.
If a small town has a 4-way stop on a quiet, desolate intersection, and the local cop writes a ticket to every out of state car, regardless of whether it came to a complete stop or not, that does not invalidate the principle of having traffic controls at intersections.
Similarly, I think it's perfectly reasonable for hikers to pay for maintenance of lands they are using and which were previously subsidized exclusively by hunters and fisherman. Whether or not those collecting the fees use the money for its intended purpose doesn't void the principle that it's wrong for some people to have full free use of what others are, and have been paying to use.