It's ungrateful to be wishing you were doing something else at the moment you are living. You haven't lived in the moment that you are really living, you are wishing you were somewhere else.
“A book is a fragile creature, it suffers the wear of time, it fears rodents, the elements and clumsy hands. so the librarian protects the books not only against mankind but also against nature and devotes his life to this war with the forces of oblivion.”