"Everyone ought to read whatever books they fucking want" isn't that useful as an intellectual opinion. Yes, fine, but what kind of books should we want to read if we want to lead our lives the best way possible? Why read at all?
That addresses the "where does it come from?" but not the "why", which I would generalize as entertainment distracts from the pursuit of a better way of living.
So where did it originally come from? Who did it or said it first? I have absolutely no idea, nor do I care. So, yeah, you're on your own. :-)
"An example of a natural but non-necessary desire is the desire for luxury food. Although food is needed for survival, one does not need a particular type of food to survive. Thus, despite his hedonism, Epicurus advocates a surprisingly ascetic way of life. Although one shouldn't spurn extravagant foods if they happen to be available, becoming dependent on such goods ultimately leads to unhappiness."
" "Alas", said the mouse, "the whole world is growing smaller every day. At the beginning it was so big that I was afraid, I kept running and running, and I was glad when I saw walls far away to the right and left, but these long walls have narrowed so quickly that I am in the last chamber already, and there in the corner stands the trap that I am running into."
"You only need to change your direction," said the cat, and ate it up. "
That is, if you're the kind of person who thinks deeply about things, looks for insights and connections, questions how things work, etc., you're going to draw some insight from a James Patterson book, or Stephen King or whatever.
OTOH, if you're not that kind of person, you can force yourself to grind through mechanically reading the words of Infinite Jest or Gravity's Rainbow, or Ulysses or Finnegan's Wake or whatever, and wind up no better off at the end than if you'd read from a random word generator for the same period of time.
edit: typo