#Because They Can

Humans are biologically hardwired to want children. Having and raising them is satisfying to most individuals. Earth is at or past the sustainable carrying capacity. An educated population understands that and looks for a relatively painless way to get the population down on the long term is to breed below the sustainment level.

If the spacers can build stations out of one asteroid, they can build stations out of many asteroids. The expansion is limited by the stationbuilding capacity. The limiting factor on that? Workers. That will work until they run out of suitable asteroids, which is a long way off.

Because They Can

Humans are biologically hardwired to want children. Having and raising them is satisfying to most individuals. Earth is at or past the sustainable carrying capacity. An educated population understands that and looks for a relatively painless way to get the population down on the long term is to breed below the sustainment level.

If the spacers can build stations out of one asteroid, they can build stations out of many asteroids. The expansion is limited by the stationbuilding capacity. The limiting factor on that? Workers. That will work until they run out of suitable asteroids, which is a long way off.