ONE aspect of duty free sales I have never understood is why the system operates at the departure terminal resulting in hundreds of passengers taking alcohol thousands of miles or drinking it surreptitiously while on board.

If the system operated at the arrival airport passengers could still avail themselves of the perk and operators would still be able to make their generous profits but without contributing to the risks posed by irresponsible drinkers on flights. Perhaps someone could enlighten me.

John Nicholls, Sedgefield