> It's already the case that work-shifts span calendar days for many people They're still only a small minority a people, though. (In Germany for example ~5 %

> It's already the case that work-shifts span calendar days for many people They're still only a small minority a people, though. (In Germany for example ~5 % of people regularly work night shifts.) Without timezones, in locations further away from the meridian a far larger number of people will suddenly be impacted. Having the calendar day change smack in the middle of waking hours of most people is rather annoying.