Mr Tojo, I accept your mild sarcasm as your argument, but at no stage did I criticise the flight-deck crew. It's the #1's/Purser's job to run a tight ship - a lot easier in my day, I would have to agree.
Despite the reply, the people selling alcohol to, often imminently boarding passengers certainly have a moral duty to act like a responsible landlord, but that's wishful thinking. In the chaos of modern air travel it's a wonder there's not more drink-related problems. The occasional scrap is bad enough but drink fuelled, deep-routed anger could lead to a major 'I hate the world/life/people' type of rage. To have the aircraft so vulnerable to a psychotic episode is bewildering in this technological age.
It is obvious that certain people must be very aware of this vulnerability.
As for the OP's point. My opinion is, the original sentence was already on the harsh side - if there was no intent. The increase is uncomfortably like American sentencing where more and more prisons are built - because with a system like that, they can afford to.