They whip them for simply standing still after finishing their work, the lash coming down or they get cursed at, driven to do something else.
For a better life in the Federation, or to better blend in with the local crowd, these people have completely set themselves against the Imperial people.
They please the Federation people by doing jobs that Federation people are unwilling to do, hence gaining recognition, acceptance, and possible opportunities.
Whether there are such people among these girls, Elvin couldn't guarantee.
Perhaps there are already girls who have "surrendered" lurking, choosing to side with Red High Heels for survival or something else.
Otherwise, why would Booker have discovered Lisa?
Bars work at night, Lisa would sleep at home during the day. After waking up, finishing her meals, it would already be evening.