Flight attendants with HoloLens – What could possibly go wrong? 

From Will HoloLens turn air travelers into mixed-reality characters? – GeekWire

Imagine a world where headset-wearing flight attendants can instantly know how you’re feeling based on a computer analysis of your facial expression.

Actually, you don’t need to imagine: That world is already in beta, thanks to Air New Zealand, Dimension Data and Microsoft HoloLens.

In May, the airline announced that it was testing HoloLens’ mixed-reality system as a tool for keeping track of passengers’ preferences in flight – for example, their favorite drink and preferred menu items. And if the imaging system picked up the telltale furrowed brow of an anxious flier, that could be noted in an annotation displayed to the flight attendant through the headset.

Google already failed at this. The only places where AR glasses would be socially accepted are those ones where personnel with equipment is the norm.

It would take years, if not decades, for people to accept the idea that flight attendants must have a special equipment to serve drinks.