Why does the dining hall at Pencey serve steak on Saturday nights?

Salinger makes the Pencey dining hall serve steak once a week simply to exeplify the classiness and wealth of that school. As you probably know, steak and sir loins are not inexpensive, so any school that would give it frequently to its students must have a good supply of money. This school then goes on to represent the trapped feelings Holden feels in life.
HOLDEN'S TRAPPED LIFE = THE TRAPPED WALLS OF PENCEY