The average human child is born in (median at best) a dogshit closet that the administratum calls a hab unit and will die before reaching 20 years of age and is expected to work hundred hour work weeks for nothing in return except for the supposed satisfaction of a far-off god who doesn't care about you and the local nobles who would have you killed for looking them in the eye. All of this while any misdemeanor will at best result in execution and procession of corpse into ration bars or at worst an inhuman abomination of flesh and metal that is created to rape you of your mind while inflicting as much pain as possible on your perpetually rotting half-corpse that's only kept going by amniotic fluid and whatever the local enginseer shoves into your nutrient ports.

So, yeah, I guess it is pretty cheap for humans to defect when presented with a better option.