At the moment I'm working in a small-ish convenience store, and while working today I served a girl, probably about 16. She bought a fizzy drink and a packet of chocolate buttons, I scanned everything, told her how much it was and she gave me her card to put into the card reader. However just as I was putting her card into the reader she opened her packet of chocolate buttons and started eating them!! Is it just me who finds it really rude when customers start eating their purchases before you've even given them their change? It happens quite frequently where I work, are they seriously so hungry that they can't wait another few seconds?!? 