Do you ever steal peoples food at work ?

I worked with a woman who was always getting snacks stolen out of the office/break area at night after we went home. she started putting them in her side drawer in her desk and half would be eaten that night. There was a guy working at night and his mother who also worked in the dept but a different area would come up all night and wait for him to get off work and we suspected it was her. Well one day the lady brought ex-lax frosted brownies and put them in a ziplock bag and stuck them in her side drawer. The next day she came to work and half of them was gone...the woman we suspected called in sick saying she had a stomach bug. And no more missing food after that.