The thing I love about A Christmas Carol is that at the time he wrote it, Christmas, as a holiday, was on par with our Arbor Day. And Scrooge held the Majority Opinion.
Dickens originally set out to write a Very Serious Pamphlet About the Plight of the Poor in Modern Times, with numbers, and statistics, and gruesome details about the state of debtors prisons. And he realized that it would probably not change a single thing, in the end.
So he changed it to fiction, and made it emotional, and focused on the lives in one specific family. And he also self-published it, because he realized that a for-profit publishing house wouldn’t want to touch it. And gave it to friends.
Not only did it help change people’s attitudes toward charity organizations and help reform labor laws, it also (pretty much) revived the whole custom of celebrating Christmas at all.
That, my friends, is the power of a well written ghost story.