Originally Posted by
studentff
So you're saying that the distressed mental state of the hostage passengers is a
justification for keeping them cooped up as prisonsers lest one or two of them run amok on the tarmac??????

Shame on you.
"Security" is not an excuse for misbehavior. Engines can be shut down, stairs can be salted and cleared of snow, and busses can run in pretty bad snow.
If the airlines had to pay pax $100 each, in cash, for each 30 minutes the plane sat over 3 hours, I guarantee you they would come up with a solution.
Can we please stop using the term "hostage." They were stuck in a plane with TV and food, so they were in an "uncomfortable and undesirable situation."
Anyway, so let's say that the ground is salted, and snow cleared, and busses ready, and they are deboarding. In the process, a person trips at the top of the stairs and pushes people into the frozen tarmac, with injuries. So, now you need emergency vehicles along with the busses to get the people away. This would be followed by a class action suit, saying that they were in a dangerous situation, and we would be here criticizing B6 for letting people out on an active taxiway in a storm.
Next, hypothetically, you shut down both engines for the passengers and disembark. But, then, the engines freeze and are unable to restart. So, if there are any planes behind the aircraft, they are stuck until a tug is able to move the aircraft. If that takes a long time, than the passengers demand to be let off, which causes more and more passengers to disembark onto the taxiway, causing even more chances for dangerous situations. Security is not an "excuse," it is a valid reason, because anything can, and will happen.