This is Walter M. Miller's “Crucifixus Etiam”.
Troffies are mentioned in the review below.
Desperate to find some sort of meaning for the work he is doing, Manue
goes to one of the “troffies” (for atrophy, the older workers who have
given up any hope of returning to Earth), who explains it to him as a
problem of overproduction and underconsumption:
“So, it’s either cut production or find an outlet. Mars is an outlet
for surplus energies, manpower, money. Mars Project keeps money
turning over, keeps everything turning over. Economist told me that.
Said if the Project folded, surplus would pile up-big depression on
Earth.”
Miller, Walter M. – “Crucifixus Etiam” (1953) - Doomsayer Press
and in the story itself.
Earth chalice, Earth blood, Earth God, Earth worshipers—with plastic
tubes in their chests and a great sickness in their hearts.
He went away saddened. There was no faith here. Faith needed familiar
surroundings, the props of culture. Here there were only swinging
picks and rumbling machinery and sloshing concrete and the clatter of
tools and the wheezing of troffies. Why? For five dollars an hour and
keep?
You can read the story online here