Loitering - the posh way to say don't drop your litter

During a discussion about Lord of the Flies I was asked by a pupil to explain the word loitering. I duly did and there was some discussion about the spelling. At that moment another pupil had an epiphany "so those 'No Loitering' signs mean we're not meant to stand around in groups? I thought it was just a posh way of saying don't litter."