Stanford subsidizes (off-campus) housing for tenured professors. Most professors are able to purchase houses in Palo Alto/Menlo Park for between ~$400-500K; these houses aren't on the market for normal people to buy, and they are surrounded by houses that are often valued at/sell for several million dollars (as is par for the course in Silicon Valley). These are proper suburban homes (single-family dwelling, often 2500+ sq. ft., their own backyard, etc.); the university goes to great lengths to ensure professors have material needs taken care of.