Why does anyone need to use a mobile whilst in the air? Why do people bring laptops to breakfast and lunch? Remember the days when you waited until you actually GOT to work to call people. The majority of calls I hear in the airport are usually "Yes, I'm AT the airport now", followed by "We've got our gate now"., to "They are calling our flight" and then "I'm just getting ON the plane". Of course you then have those 'these-rules-don't-apply-to-me' types who think putting their phone on mute is the same as turning it off, and they continue to text throughout the flight.
No-body is that important that they need to have CONTINUOUS contact with the office/home. If that were true, businesses would have fallen over years ago, when we relied on the post. But they didn't.