"I think we're saying, 'Let the restaurant operator worry about having fresh bread, fresh tomatoes, fresh lettuce, fresh meat,'" said Balzer.

Nancy Childs, professor of food marketing at St. Joseph's University, was pleased to see a report on what "we intuitively know is happening everywhere." The finding that just more than half of the 50,000 meal preparers surveyed want dinner to be easy to make, with little or no planning, is in line with what she sees happening in the American home.

"One of the things we overlook is that people do want to create variety," said Childs. "With a sandwich you can be creative. You can use pita, panini, a slice of bread or a roll. Content can be enhanced not only with tomato, lettuce and cheese, but with other vegetables. People are putting apples and pears in sandwiches."

While Americans continue to seek ways to address their health and food safety issues, Balzer said, "healthy eating will take hold when it is either easier or cheaper to do than what we do now."

Along that line, Childs said, the sandwich "enables us to meet individual needs. Kids today are used to ordering dinner off a menu." That means meal preparers can cater to each family member, she said, including children that are vegetarians or vegans.

Dinner sandwiches, she said, satisfy a hidden expectation: basic ingredients made by hand by the ideal mother or grandmother, updated for the 21st century.