I think some industries, like housing, healthcare, banking, etc should be primarily not-for-profit. Not-for-profit companies are not hypothetical or theoretical, they exist, right now, today. Credit unions are a good example, but not-for-profit companies exist in many different industries. Intermountain Health is a not-for-profit healthcare system in the Mountain West, and they have nearly 400 clinics and over 30 hospitals. They employ 64,000 people. During his presidency, Obama mentioned them as a model for healthcare, as they are able to offer high quality healthcare that is often less expensive than other for-profit offerings.
It's important to note that not-for-profit is different from non-profit. A non-profit is not allowed to have a surplus at the end of the year, whereas a not-for-profit is. However, unlike a typical for-profit companies, not-for-profits don't distribute their surplus (profit) to owners, they reinvest it into the company.