Here's a great justification for varnishing the truth, which I'll summarize for your convenience (though of course the original passage is superior):
1. varnish brings out veins of beauty that were otherwise invisible
2. it doesn't actually hide the sober facts of life since it's transparent
3. having penetrated the artifice, the observer's powers of insight are flattered and attention is better secured
4. even the coarsest mundanity has moods in which it's gilded by the light of romance
5. if the storyteller believes in the true gold of those fairy minarets, the story benefits
From
Idolatry by Julian Hawthorne, 1874.