The life of the olive mill owner is one which is cast in shadow as they is invariably cast as an untrustful character.
They will 'cook' your olives so as to extract more oil in which case they get paid more for the milling. They have a secret pipe that siphons off your oil during the process or they are just don't pay you. These are amoung the kinder ones.
This is an oft repeated conversation between olive growers this time of year as one of the stock conversation pieces is "and what mill did you use"?