Cards Against Humanity, the hit game sold only on Amazon (although a significant number of retailers buy it on Amazon and mark it up to stock in their stores, see “Rolling for Initiative—‘CAH’”), has sold nearly 500,000 copies, according to an article about the company on Chicago Grid.  Over 1.5 million PDFs of the cards have been downloaded free from the company’s site.  And it’s done this with no management structure and all eight of the company’s twenty-something owners still working at day jobs. 

The game started with a $15,570 Kickstarter, which funded the first 2000 copies back in late 2010.  Since then sales on the core game have been growing rapidly, and three expansions have also been published. 

The founders have spurned approaches by game companies, venture capital firms, and licensing companies, preferring to keep their operations simple and self-funded, according to the report.  And no big companies have produced knock-off games, perhaps scared off by the game’s edgy content.
So for now, Cards Against Humanity remains the hottest game you can’t get at trade discounts, but it’s still a significant seller at stores that buy it at retail and mark it up.