Notice that this post is filed under "Economics."
The airlines fear "crowd control" problems if cell phones are allowed
in flights. They believe cell phone calls might promote rude behavior
and conflict between passengers, which flight attendants would have to
deal with. The airlines also benefit in general from passengers
remaining ignorant about what’s happening on the ground during flights,
including personal problems, terrorist attacks, plane crashes and other
information that might upset passengers.
This is also relevant:
However, the airlines know that some kind of plane-to-ground
communication is coming, and they want to profit from it. Simply
allowing passengers to use their own cell phones in flight would leave
the airlines out of the profit-taking. Airlines would prefer that
phones be banned while they come up with new ways to charge for
communication, such as the coming wave of Wi-Fi access. Meanwhile, the
ban is potentially more profitable.
Here is more.