That's so utterly absurd. So now I know that it's also 20:00Z on the other side of the ocean. Great. But, are they awake at 20:00Z there? Or asleep? Let me subtract the time difference...
I think it's mostly a sentiment from people who don't travel--or don't really communicate with other timezones at all. I need to know that someone in Europe is about 5 or 6 hours ahead of me whether it's a timezone or an informal UTC offset. And if I'm traveling, while there are cultural differences between countries (e.g. later dinners in Spain), I know that the workday is something roughly 9-5 and dinner is roughly around 7pm.