There is a little disparity in the story. The story indicates that "None of the cabins are ever locked. They are open for anyone's use."
And yet, the sign inside Liber's says his unlocked cabin is here for the use of:
1) Those who built it.
2) Those who work to keep it.
3) Those who are invited.
I'm not saying he does not have those rights, because he does. I'm just saying, if I go in and read that sign, I'd feel unwelcome and that I'm trespassing.