I am always amazed how many people are in the bar at half past five in the morning at the airport, I can not think of many other things that I find so un-appealling as an alcoholic drink at that time of the day.
It's all peer pressure and male bravado - I've seen groups of lads getting out of a minibus outside the airport at 4:30am, all with a can of beer in their hand all trying to 'prove themselves' as men to one another.