From an airport's commercial viewpoint, the yellow brick road really does work. It never ceases to amaze me how much money people will pay for overpriced rubbish at airports and on an aircraft - it's almost as if the desire to find bargains that exists when shopping normally, completely disappears and pax instead desire to be ripped off with expensive shiny beads. Large numbers of the pax (including Mrs Johnson) at airports do not fly every week, and really do enjoy the whole retail experience.