When you see luxury condos, they so often appear uninhabited. At least, you rarely see someone at the window, or on the balcony or in the drive. Seaside residences are like this too. Walk the beach, look up at the multimillion dollar homes, rarely anyone home.

Is this because those properties remain unsold? The real estate is too expensive for you, maybe nobody can afford them? Hardly. This phenomenon has to do with what separates affluence from the rest of us. Those who can afford million dollar lofts, condos, or estates, can afford several. They’re only ever 25% home. When they shop, they buy multiples of everything for each home, lest they have to pack between trips.

One of my favorite show-biz verite moments is captured on Randy Newman’s concert album Live at the Paladium. During an instrumental segue, Newman attempted to make small talk with Linda Ronstadt, with whom he was singing a duet. “How many houses do you have?” he asked her. Ronstad offered only a smile as Newman kept playing. “You know, most of these people only have one home.”