@1: I believe that was to convey just how long Sam has already been in the Citadel, and how little progress he's made toward his goal of finding info to fight the White Walkers. Hence his need to (temporarily?) pilfer some books from the restricted section of the library. I expect this will lay the groundwork for his expulsion, which will heighten the tension about whether humanity will find the resources they need to win.
Besides, it provided a moment of levity, in a season that's probably not going to have a whole lot more.
Just when you thought Theon couldn't suffer any greater indignity: not even a glimpse of him (or Yara) in the final season opener. Or did I miss something? Was anyone else of note conspicuously absent?
Besides, it provided a moment of levity, in a season that's probably not going to have a whole lot more.