So Fidelity unveiled two new index funds Wednesday to individual investors with a zero expense ratio, a move that roiled fellow asset managers. Fidelity may use the funds, as well as the other index products it reduced prices on, to attract investors to more profitable businesses such as financial advice and higher-priced active vehicles. “For a number of companies, not just Fidelity, these passive assets are a loss leader,” said Kevin McDevitt, an analyst at Morningstar Inc. “It is a way of bringing in assets and selling other services, especially financial advice.”

https://www.bloomberg.com/news/articles/2018-08-01/fidelity-to-offer-index-mutual-funds-with-zero-expense-ratio