The time difference grows over fairly small distances. If you go to nearby city, it can be 15 minutes difference. That is the difference of missing an event or

The time difference grows over fairly small distances. If you go to nearby city, it can be 15 minutes difference. That is the difference of missing an event or shop being open. There are lots of things that are accurate to the minute. If you are a minute late, you miss your bus. Also, what time does the bus use? Does it change time as it moves or keep consistent time? The coordination basically requires computers. All watches need to have GPS. All computers need to have GPS. Every event requires someone to enter the official time/location. It would be impossible to accurately schedule anything over the phone. Local solar time wouldn't be for humans but for computers. Humans invented time zones because of the problem with local solar time for railroads. We much prefer consistent time zones for day-to-day.