SAN FRANCISCO — Daniel Lurie is rich. Really rich. But you wouldn’t know that from looking at him.

At a recent Halloween block party in the Castro neighborhood in San Francisco, the billionaire heir to the Levi Strauss fortune and Democratic mayoral candidate showed up in a wrinkled, white button-down shirt, some dark blue slacks, and well-worn shoes. It was his eighth stop of the day. If he was exhausted, he didn’t show it.