The landower possesses all of the power in this scenario. The people who work for him are kept in the dark about the arrangements made with other workers -- a practice we see in the modern workplace, with policies forbidding people from discussing their wages with co-workers. The wage earners have limited information and are forced to accept without complaint the landowner's response of, "Well, you agreed to work all day for one denarius, and that's what i'm paying you, so why are you complaining?"