Rule: Don’t pass the pepper when I only asked for the salt.
Contrary to popular opinion, the salt and pepper shakers are not an inseparable couple. Although most of their time is spent together during non-dining hours, when mealtime arrives they are each capable of complete autonomy.

Why complicate things?
When I politely say, “please pass the salt”, the salt is precisely what I expect to receive. If you pass both the salt and the pepper, I am required to forgo my initial plan to efficiently transition from receiving the salt to salting my food in one smooth motion. Now I must first place the pepper on the table before proceeding. And depending on the shakers, I might even have to use two hands to receive the pair of them.
There will be no confusion if the salt and pepper remain separated. If someone later asks for both the salt and the pepper the diners nearest to each one will gladly hand them to you.
This is an instance where conventional etiquette leads to less efficiency, particularly because the salt is used far more frequently than the pepper. It is true that the requester must remember to append the phrase “and pepper” to his request when both the salt and pepper are needed, but that is a small price to pay in comparison to requiring everyone to unnecessarily haul around twice the weight and number of objects each time someone asks for the salt.
Exceptions
- This rule is not applicable when the salt and pepper are housed in a single unit.
- If the salt and pepper shakers are housed in a single holster that can be easily lifted and passed, it is okay to pass the entire unit.