It's not about selling internet to people, certainly not initially. The money here is in bringing internet to sophisticated entities in isolated areas. Networked industrial control systems, mines, drilling operations, shipping, etc.
Roughly paraphrased quote from Elon Musk SpaceX Seattle Office Opening: "The speed of light in vacuum is 40-50% faster than in fiber. So you can do long distance communication through space(vacuum), a lot better than if you route it through fiber and use far fewer hops. Lets say you want to communicate from Seattle to South Africa, the path is extremely convoluted, follows outline of continent, goes through 200 routers and repeaters, if done with satellite network, it can be done in 4 hops"
Video link to time of quote -> https://youtu.be/AHeZHyOnsm4?t=209