in a previous job a driver i barely knew [different company] pulled up as i was about to go home from the yard ,offered to fill up my car with diesel from a drum in his truck . he was quite pushy about it and i meekly let him do it . he bragged he that since starting work there few years previous he had never bought a drop and he had a Discovery + wifes car running on it .
few weeks later he tried again but this time i said no and he never pushed it . i later gave it some thought and reckon he is a very cunning thief who covers his own back by involving others .
And you fell for it hook, line and sinker 
I know a day man who takes a 2 litre bottle of pop to work everyday ,when he fuels up the end of the shift he he nicks 2 litre of diesel[thats every day]with out fail,not be long before hes caught ,too many people know what hes up to and he sometimes reaks of diesel
im really naive like that . it took me ages,months, to twig that was why he gave it me, i thought it was simply a friendly gesture.
i only realized it when i went to a BBQ at his place, and he took me into his garage to get me a beer- he had a commercial fridge fully stocked with beer.Also his garage was full of brand new tools that had never been used, he offered me some spanners which i declined . thing is his boss was there too , not actually in the garage, but a stones throw away-sitting by the pool