I always thought the movie failed because large groups of intelligent humans just don't behave like that when money is the prime motivator.
Money might not have been the primary motivator for everyone there (just a part of their reasoning). The end of the movie's voice over did say that the human's were being sent back to their "dying planet."
Most of the troops, engineers and laborers would have family, homes and friends back home, the floating rock would secure their love ones well being and life styles.
There could also be the adventure aspect of traveling to a distant alien planet.
(or I misunderstood what you meant by "like that