Some people just don't get what honesty is.
Where I once worked they sacked a guy over something very similar. It wasn't the fiddle (which was about £10) but eventually his angry insistence that it was just fine to do it couldn't be accepted. I had a guy that was always fiddling his mileage claims in a really stupid way. Didn't sack him but he knew I knew he knew I knew and my secretary would delight in throwing his claims back at him.
Best one was a guy when I worked on the buildings one summer, was always nicking matchboxes so we would leave boxes full of spent matches for him to nick. Couldn't sack him, we were always playing cards for money in breaks and he was that 'if you're playing poker and you haven't worked out in 30 minutes who's the mug then it's you' mug that supplemented our wages.
