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.

I've eaten/drank parts of co-workers lunches unwittingly thinking they were part of the community food/beverage selection.

I never got reprimanded, but I did have to sheepishly explain to a coworker that I drank his soda thinking it was one of the community ones since it was in the door of the fridge and unmarked.

I now work at a company with an extensive free kitchen and you have to do an extremely good job of marking your personal food since the default assumption will now be that the food is everyones.

Same lunch box as someone else. In an office of 7 people, I had the same lunch box as two coworkers. Have someone else make your lunch or bring a generic enough item and it could happen.

Honest mixups happen and when they are followed up with an apology then it's fine. Let common sense prevail.

This happens occasionally at my work, and I'm pretty sure it is always accidental - but it is because we get food delivered every day, and a combination of food not being very well labeled, orders getting messed up, and people forgetting what they ordered that day - things get mixed up.

That said, I really can't imagine any situation where it is reasonable if you are talking about people's homemade lunches, in a well labeled lunch box - as is the case in this story.

There's company paid lunch where the leftovers are put into the fridge for people to take it later before throwing it out. A coworker puts their own food into the fridge without putting their name on it. You take your coworkers food thinking it was leftovers from lunch.

A whole lunch may be a bit much unless it’s some sort of pre-packaged food, but a few I have seen over the years:

- Grab-and-go sandwich from local vendor was eaten by wrong person. They had a similarly wrapped sandwich in the same refrigerator.

- Identical brands of yogurt, milk, cream, etc. were used by a non-owner with a similar bottle.

- Similar fruit was taken.

- Identical brand peanut butter was used by the non-owner.

None of these other than maybe the sandwich are like the original post, but these mistakes do happen.

In these cases, it was always resolved with an “oops, sorry” and a replacement item (sometimes waved off)... and usually more deliberate bespoke labeling or containering of common items.

Takeout box is the same and food is similar. I have the same container and it isn't labeled. Food got moved around. Forgot I didn't bring food that day.

I've caught myself once or twice where I grabbed the wrong thing. But sometimes in a rush, in sleep addled daze, or just not paying attention, it could happen. I would hate to be fired for a mistake like that.

One comes to mind for me. At my office, people will often leave snacks, leftovers, or just food for the office on a table for anyone to take. It's within the realm of possibility that someone may leave their lunch unattended on the table and a passerby may think it's up for grabs.

Here's mine: https://news.ycombinator.com/item?id=16959980