The benefits of allowing people to make money by starting businesses are a separate discussion. I only meant to say that insurance companies are already legally

The benefits of allowing people to make money by starting businesses are a separate discussion. I only meant to say that insurance companies are already legally prohibited from making "insane profits". But to answer your question, there are many people looking to invest their time and money into profitable enterprises. Because insurance is a good that is very beneficial for society, we want people to invest in making it a thing. Therefore, we set up a system where the people who invested in its creation get a tiny fraction of the benefit it generates. There are many areas of life where this works great, like providing food and shelter, and I guess it wasn't obvious that insurance would be an exception for some reason.