You mean they in average of 7 days work over 12 hours a day? hmmm...
14 hours a day Monday to Friday, including maybe an all nighter mid week, with a few hours stuffed in on the weekend, could easily add up to circa 85 hours a week.
Why do you think those shoebox sized flats in London are worth so much money? A lot of these City types literally don't have time to commute.
I remember going to a friends party in a flat overlooking Docklands. He, and most of the guests were doctors. I met a locum GP who was in a similar situation to me-paid a lot of money for relatively little work and we both looked at Canary Wharf on a Sunday evening discussing whether we regretted not going after the bigger money available in finance. The GP said, "it's Sunday evening and look, all the lights are on in Canary Wharf, I wonder why...".