A definition of evil coming from 1st edition AD&D is someone who puts their own personal gain ahead of the wellbeing other people. They don't necessarily WANT to hurt other people, but they won't hesitate to do do if they get in their way.
And, by that definition, there are a great many evil people in the world.
Now, traditional fairy tales aren't a good guide for D&D - the game's original creators tried to put as much space between D&D and traditional fairy tales as they could. Traditional D&D is "Swords and Sorcery" or, later "Heroic Fantasy", not a fairy tale.
But If you want to discuss fairly tales, a common theme is a protagonist who behaves selfishly, and either learns their lesson or gets their comeuppance. Thoroughly "Good" protagonists are more a feature of the Heroic Fantasy sub-genre.
