A guy that worked for me years ago had an earlier Job at Douglas Aviation working on DC-10’s.
He took his Lunch to work every day and put it in the Staff Room Refrigerator. After his Lunch mysteriously disappeared a few times, his Wife put a Dog Food Sandwich in his Lunch.
He put in in the Refrigerator at work and the next day it also mysteriously disappeared.
After that his Lunch was never stolen again. #;^)
So, it wasn’t a dog that stole his lunch?