It's not only their TV show "Keeping Up With The Kardashians". They have multiple business ventures that you will be surprised to learn in the following article.
Their dad, Robert Kardashian, was already a wealthy lawyer from Beverly Hills, famous for defending O.J Simpson and having friends like the Hilton's. After his death, Kris Jenner married Bruce Jenner (now Caitlyn Jenner) who was a gold winning athlete and a TV star personality.
Kim Kardashian became famous for her intimate tape, and she won a lot of money from suing the company that exposed it and for the magazines and shows like Dancing With The Stars she starred afterwards. She later won almost $20 million for licensing her former marriage to NBA basketball player Kris Humphries (lasted only 2 months).
After the family reality TV show #KUWTK, they managed to start other lines of business like fashion boutiques, clothing (DASH), child fashion, jewelry and fragrances brands. They also went into the food business promoting candies and liqueurs.
Of course, the list wouldn't be complete without the mobile app called Hollywood, a book and several other spin off TV shows where they might appear from now and then. One clear example is the show "Flip It Like Disick" from E! Entertainment Television where former husband from Kourtney Kardashian renovates homes.
Let’s not forget they earn also from their social networks. In 2019, Kylie Jenner, according to Hopper HQ tool was the highest-paid Instagram influencer in the world earning approximately $1 million dollars per post. Not bad right?