They open a new checkout.
You then peel off the back, round the lollies and the magazines and go straight in as number 1 on the new checkout, thereby getting served straight away when those of us who have been waiting fume as you exit the building.
In this situation, I both dislike you, and respect you. Because if you reverse the roles, I’m probably going to do exactly what you did. All's fair in love and supermarket shopping.