Natural-born vendactors

I'm watching some woman selling flowers on the street. She spots a young couple and swoops on them, waving her bunch of roses. The smile on her face is the brightest, happiest, most piercing smile you've ever seen.

The moment she realizes the couple isn't going to buy, that smile vanishes, just like that, all at once, without leaving a trace on a face that has instantly reconfigured itself into a scowl carved in marble.

With every new pair of potential customers, the ritual of swapping "masks" repeats. A change so abrupt, from one extreme setup to the other, so sudden and clean that you couldn't say which of the two "moods" the girl actually identifies with.

How the fuck do they do it?
Natural-born vendactors.

Drafted from Italian with Blog Translator, then revised by me.