Via Pardon my English a little turn up for the books. Businessmen, those representatives of trade and thus not on the level of gentlemen, seem to have grasped an important point:

Eight soldiers flying home from Iraq for two weeks of R&R flew in style instead of coach after first-class passengers offered to swap seats with them.
“The soldiers were very, very happy, and the whole aircraft had a different feeling,” flight attendant Lorrie Gammon told The Dallas Morning News in Thursday’s editions.
The June 29 seat-swap on American Airlines Flight 866 from Atlanta to Chicago started before boarding, when a businessman approached one of the soldiers and traded his seat.
When the swapping was done, “the other two first-class passengers wanted to give up their seats, too, but they couldn’t find any more soldiers,” Gammon said.

To those two first class passengers who could not find a soldier to swap with, my advice is “get your gratitude in early”.