Not having a spare is definitely a problem when you need it. But a spare is needed so rarely today. And that is a major, major advance. One hundred years ago,

Not having a spare is definitely a problem when you need it. But a spare is needed so rarely today. And that is a major, major advance. One hundred years ago, a car with two spare tires were not that unusual--tires were sufficiently unreliable that you might not manage a trip without _two_ flats, but tires improved, and now the only long-overland back-country adventurers carry two.