This picture made me recall something I heard last weekend about the Spanish military academy
. It's a fact that they go to speeches mainly to sleep, if only because they are taught to sleep when they can. But not everybody can sleep. There is an unwritten law that orders how students sit at the lecture hall: freshmen at the front rows, second year student at the middle, and 5th year students at the end of the hall (3rd and 4th year are taken at academies that are specific for each Army branch).
Thus, only those in the middle and back rows are allowed to take a nap; freshmen are not, and 2nd year are not either, but they do it sometimes.
Which takes us to the picture: those who are asleep are probably veterans, and those who seem to be listening are probably freshmen, just arrived from civil life.