C'mon people, they're just trying to do their jobs! Protecting princesses in castles from unwanted visitors! Napping in their lair on piles of treasure that would surely collapse the world economy if it were to be released into the stream of commerce!
And then, wham! Here comes a knight with a disregard for royal etiquette and economic stability, and suddenly the dragon is out of a place to live. Won't you give him a home? He promises to guard all your princesses and extra monetary capitol.