Maybe they merely enjoy the exhilarating ego trip associated with lying so successfully. I am not afraid to admit I get a distinct kick out of pulling something over on someone. This ecstasy increases with the number of people duped and the number of people involved in the duping. And I know I am not the only mischevious person on the planet. Certainly the Easter Bunny and all his imaginary friends exemplify the ultimate betrayal of trust.
Children know nothing about the world except what they learn about it from others.
Adults twist this trust as they perform pernicious acts of deceit. The whole world works hard to con an entire generation. Naturally, children grow to question the validity of what they have been told. I have ever heard. He explained in a lengthy dissertation that the flashlight represents the sun, and the globe the earth.