I am looking for a short story from the 50s or early 60s. I think it was Richard Matheson but I'm not sure.
A man is on a car trip and comes to realize that he is completely alone, no people anywhere. He travels on for about 2 days, and then everyone suddenly returns with no explanation; people seem somewhat disoriented but otherwise OK.
He later remembers that his son, when he was young, moved his pet fish from one tank to another identical tank, but then moved them back because he thought they were happier in the old one. The man figures that "someone" did the same kind of thing with people, but he was driving through a tunnel at the time so he didn't get moved.
If anyone recognizes this story, do you know the title?