There is still the promise of potentially being freed after some time and most people who were there believed to some extent that they deserved to be punished f

There is still the promise of potentially being freed after some time and most people who were there believed to some extent that they deserved to be punished for being a bad communist. If the class difference is big, the narrative to justify the difference must be strong; even under serfdom or slavery, there were uprisings when the narrative was weak. The lowest class has to be (to some degree) content with their situation.