Why do we read? Many people seem to assume that the only reason for reading is to obtain information about the world. With this view, reading fiction is perhaps hard to justify. But if one only reads to learn new facts, then one’s life is impoverished and Gradgrindian. Indeed, this reason strikes me as like learning to play the trumpet in order to have a means to practice circular breathing.
In fact, we read for many other reasons than just this one. One could say we primarily read novels for the pleasure that reading them provides:

• the pleasure of reading poetic text (as in the novels of Hardy, Joyce or Faulkner, for instance)
• the pleasure of reading elegant, finely-crafted prose (eg, Fanny Burney, Doris Lessing, Perec, Brautigan, the English translations of the books by Zhores and Roy Medvedev)
• the pleasure of engaging in deductive reasoning (any detective or espionage novel)
• the pleasure of imagining alternative societal futures (scifi), presents (political thrillers, espionage novels), or pasts (historical fiction)
• the pleasure of being scared (crime thrillers, horror stories)
• or the pleasure of parsing an intricate narrative structure (eg, Calvino, Fowles, Murnane, Pynchon).

These various pleasures are very distinct, and are orthogonal to the desire to gain information about the world. And some of these pleasures may also be gained from reading non-fiction, for example the finely-honed journalism of Lafcadio Hearn or AJ Liebling or Christopher Hitchens, or the writing of Oliver Sacks, who passed on today.