Why is this coffee vending machine special?

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It gives you free coffee when you yawn! Yes, in order to promote itself as the Number One coffee brand for all those sleepyheads, Dutch coffee brand Douwe Egberts installed a very special vending machine in South Africa’s O. R. Tambo International Airport that gives you coffee when you yawn in front of it.

According to Gawker, using built-in facial recognition software, the machine was innovatively able to detect over 200 yawns and distribute free ‘wake-up’ juice correspondingly.
There are some who have expressed concerns over the idea of a creepy vending machine that’s able to read your face while you’re walking by — but then again, when there’s free coffee involved, who can have too many complaints?
It remains to be seen if more such machines would be installed in outlets across the world, but one can;t argue that this would be an extremely successful marketing gimmick indeed.