Maybe you've heard the stories; One person talking to another, "Hey want to try this board game that just came out? " Other person, "Oh, it has dragons....yeah I'm not really in to fantasy stuff. How about we play Cards Against Humanity?"
A lot of the games in the hobby market have strong themes that appeal to crowds accepting of those themes. I'm talking about dragons, space ships, pirates, samurai, etc. However there are millions of people out there that prefer non "geeky" themes, but still appreciate a bit of humour. The financial success of games like Exploding Kittens, Cards Against Humanity, and Fluxx are some of the more common examples.