Moira does escape working at the toxic dump by agreeing to work at the house of prostitution, Jezebel's, but it would be difficult to consider her the same rebellious spirit that we see her at the beginning of the story. Her clothes are tattered, she and the other women use drugs, and she is as much as a "whore" as the handmaid who are used for purposes of breeding. Rather than rebellious and victorious at the end, Moira is beaten. In saying she has a good life it is more likely she is speaking out of desperation or because she is told to say that or her life would be even worse. She is important in the novel because she demonstrates the strength of the party--how it can reduce even a woman of rebellious strength to a worn woman dressed in a tattered bunny costume. She is every bit as much of a sexual object as those forced to be vessels for pregnancy--maybe even more so. She shows the difficulty of escape this sexual totalitarian society.
Moira is important to show the difficulties in the resistance movement in totalitarianism.
She is sexually uninhibited in her homosexuality in a sexually repressed society, and is punished for it. It does not stop her resistance, and she tries to escape, but is mutilated.
She escapes again, and is forced into prostitution. Yet, through it all, she does not let them beat her into submission.