strange thought of tody

Classic dialogue from an unjustly forgotten movie; this stands up with the best the Coen brothers have produced.

Cedric the Entertainer - "They never grow up, lady.They just get tubby." (referring to cheating husbands)
Catherine Zeta-Jones - "How charming. An aphorist."
CTE - "Oh, yeah, I've always had ample proportions. But believe you me, it's all muscle. I'm as hard as a rock. ... Gus Petch don't pussyfoot around."
CZ-J - "I must say, for someone in your line of work, you don't exhibit a great deal of tact."
CTE - "You want tact, call a tactician. You want an ass nailed, you call Gus Petch."

Why do people so this?

I can't figure it out. Why do people underline and make notes in a unviersity library book? What is especially annoying is that the person knows it's a library books, knows they shouldn't put pen marks in a library book, but goes ahead and does it anyway. Why? Why? The arrogance of these people.

I must also admit that sometimes notes in books are funny. I am now looking at a table of contents for a translation of Aristotle's Physics, and written next to 'COMMENTARY' is 'or, obscurum per obscurius'.