Display of body language mastery

[Alvar]

I was at the airport store getting ready to pay for a couple of bottles when the cashier tells me "Good morning, this cash(eng: lane?) is closed". This is a fairly polite reminder but her body language told me another story. She looked at me, her black eyes wide open, with an expression of contempt in her face and the tone of voice made me feel like I was an idiot. I actually felt a "neurological"(?) sting in my brain, as if she said "you moron, how dare you waist my time". But it was worse because I could not acknowledge it or even reply. Fortunately it only took me a couple of seconds for me to be aware and understand her action as a defence mechanism, even if very offensive in nature.

Do you guys notice these kind of messages, or even broadcasting yourselves?