it's that flying normally turns some of us into teetotallers
Indeed that is the right way to look at it.
It can be the occasion for mild embarrassment. In the local pub of a Friday night the landlady expects me to order my usual pint, and has been known to ask why I'm drinking grapefruit juice. "Er, because I'm going flying tomorrow" may not be the answer I wish to give in a pub full of my constituents, some of whom might think I'm not the right person to represent them on the council - if I'm so stinking rich that I can afford to fly I can't possibly understand their life circumstances, can I.