Bava Metzia 75: The Halacha of Hillel

The last daf of the fifth perek wraps up the discussion of interest with two final mishnahs. The Genara after the first mishnah shares an opinion if Hillel that is not followed. Why does the Gemara share this opinion? The second mishnah discusses multiple transactions that could be seen as having an interest payment. The perek ends with a discussion of three groups of people who cannot find justice in the courts.