How are they treated?

I assume you are referring to the apprentices. Vanka is driven by a rather straightforward scenario: Vanka is tormented by his lifestyle as one of Alyakhin's apprentices, and longs to escape back into a more welcoming and nurturing community. Already central to the plot, the theme of suffering is emphasized again and again in Vanka's descriptions, which capture suffering in a stunning variety of forms. Beatings, hunger, mockery, and exploitation are but a few of the sufferings that Vanka endures, though underlying all these is the psychological suffering of isolation, loneliness, and desperation characteristic of much of Vanka's mental life.