Modern society, as a whole, tends toward a sort of institutional optimism, espousing Hegelian notions of history as progress and encouraging us to believe happiness is at least potentially available for all, if only we would pull together in a reasonable manner. Hence the kind of truth pessimists tell us will always be a subversive truth.
We in America all know that the myth of meritocracy is just a myth. But we continue to perpetuate it in conversation, still want to hope. When you really think about the stunningly lethal social stratification that starts happening as soon as a child enters our educational systems ... pessimists are subversive indeed.
Then again, there's the other simpler answer: "I'm better off than THIS SCHMUCK. That makes my DAY."