I do not argue that freedom of movement is useful, desirable, and balanced at 18th level. I'm just saying, isn't it strange? Some guy in a beaverskin cap wandering around, who absolutely cannot be grappled. It's not a supernatural ability. It is simply impossible for something to grab him because he is so darned mobile. The kraken? Can't do it. Reaping mauler? Nope.
In fact, even if you sneaked up on him while he was asleep and pinned him, he would escape. In fact, he is immune even while he is asleep. If a basilisk petrified him, he would still be immune to grappling. It is physically impossible to grapple him.
This is also one of several organic character growth problems with the Scout... I hope you didn't spend too many ranks on Escape Artist, because you won't need them, now. (Another issue would be access to bonus feats that help you fight in darkness, which if you took, would be superceded at 10th level by blindsense).