It's close to dinnertime, and you already know what you want. There's a pizza place you like within walking distance, so you place an order online. You're too hungry to go for something adventurous because if it's underwhelming, then the hunger will make you feel worse about the decision, so you settle on a reliable Margherita pie—basically the go-to order at this particular restaurant. It'll be ready in 20–25 minutes. Great.
After about 10 of those minutes, you're antsy, and it's nice outside, so you start walking over with the understanding that it won't be ready by the time you get there. You arrive a few minutes early, and there are a healthy number of seated tables, and a couple people ahead of you, but it's not slammed. You give your name, on the off-chance that the estimation was wrong, but you're told it'll be five more minutes. No problem; you knew this going in. You wait outside, away from the entrance, in a little unofficial area where people wait for their pickup orders.
Five minutes pass. Ten minutes. Fifteen minutes. This is weird, because your order wasn't too complex, and the host at the front of the house definitely told you five minutes. Maybe something unexpected happened; someone else could have sent back their pizza and jammed the kitchen. Still, it's not a big deal. The weather's pleasant, and you merely have to stand outside looking at your fantasy baseball team for longer than you had expected.
After about 20 minutes, the host brings you a box, apologizing for the wait. "No problem," you say, because you're a cool customer. You're not like other customers. You begin the walk home, but within seconds—you've just turned the corner and are about 50 feet from the restaurant—you notice that the box is heavier than you'd expect a Margherita pizza to be. It has someone else's name (Harper?) written on the top. It smells amazing. You crack open the box and discover that this is definitely not a Margherita. Goddamn. You've had this pizza before. It's a few dollars more than a Margherita, and it has an incredible lineup of toppings. It is not the pizza you ordered. It is decidedly better.
You turn around, ready to inform the server of your mistake. However ... would they know? Would they care? Isn't there an unwritten rule in restaurants that you can't re-serve takeout orders once they've left the building? Would that mean you returned a pizza only for that beautiful, topping-filled pie to be tossed into the garbage? Your well-intentioned honesty could result in needless waste.
On the other hand ... it's been only a minute, at most. There's no way someone could do anything sinister to a pizza that quickly. You're still in the window of time where you could smoothly inform the host of the mixup and get that pizza back to Harper. Besides, if you take this pizza, what would happen to your lovely Margherita? Would it sit on a table somewhere, shivering, waiting for a suitor who will never arrive? Would poor, sweet Margherita be dealt a cruel end instead? Would Harper have to wait longer? Also, you go to this pizza place a lot and don't want to earn a bad reputation by taking a pizza that didn't belong to you.
You have a choice to make: Return the pizza that wasn't yours, correcting the error but possibly sentencing your unexpected pie to death by dumpster? Or keep your inadvertent upgrade, leaving your original order to a similar fate?