I am reminded of an old-time scientist, who was Chairman of the Department. One rule of the library was that anyone walking out of the room with a book that he has not signed for will be fined $5 on the spot (that was in 1964, so you can estimate today's equivalent.) One day the Professor was reading in the library, when his Secretary called him out to meet an important visitor. The Professor absent-mindedly walked out with the book in his hand, but realized his mistake as soon as he was out of the door. He want back and paid the fine of $5.
It was an exalting experience, because the Professor had donated his entire personal collection of science journals and books to the department library, and the book that he took out was originally his own.