Having received an unearned windfall, we are in debt. The moral scales are out of balance. The canonical way to restore a measure of balance is to return the favor to our benefactor, as per symmetrical reciprocity. However, the canonical way is not the only way. Another way is to pass the favor on, as per transitive reciprocity.

Of all trades and arts in repute or possession, / Humbugging is held the most ancient profession. / Twixt nations, and parties, and state politicians, / Prim shopkeepers, jobbers, smooth lawyers, physicians, / Of worth and of wisdom the trial and test / Is—mark ye, my friends!—who shall humbug the best.

to gas thread

It was a long time before he could steady his nerves to answer my questions, and then he answered perplexingly and brokenly.