Just to compare apples to insurance here, the largest pure auto insurer (progressive) maintains ~5-6% profit margins according to filings, whereas Wellpoint one of the largest insurers in healthcare maintains a 7% margin.

There's more to "the system" than just insurers. The large number of middlemen all extracting a profit is one of the many problems. Don't forget overhead and their middlemen, all the way back to med school tuition...