Sure! I have worked in a lot of offices over the years, and most of these have actually happened at least once:
- Someone tells another coworker they can have their lunch, but they grab the wrong one (because the tag fell off or they didn't see the label)
- Someone says there is leftover food available in the kitchen after some catered meal, and the person didn't realize that container wasn't part of it.
- A new employee got confused about which refrigerator is the 'office stocked one' and which one is the 'personal items one'
- It was fridge cleaning day, and the person thought the food was getting tossed out anyway, so they ate it. Turns out the person was going to eat it that day (this one is borderline, not only because it is kinda gross but also kinda not cool)
- Two people had similar lunches and they just grabbed the wrong one without paying a ton of attention (much more common when a group of people go out to lunch together and come back with leftovers)
- A loose, packaged food item got knocked over and fell into someone else's food container.
Some of these are probably pretty rare, but I have seen many of them happen.