I disagree. If I make an appointment for a meeting I'm flying to, 5 timezones away, it's better to be able to say 'let's meet at 9am' rather than having to look up what time '2 hours after getting out of bed' is in that particular location. Similarly, if I read news about Japan that says 'an explosion occurred at 10pm' I prefer to know that that means 'after the regular working day' instead of having to look up when the working day ends there.