kindness v. prestige in yale greek life

Why is it that Yalies often promote political progressive values such as egalitarianism but respect the meanest fraternities and sororities st the top while considering the nice sororities and fraternities as bottom tier?
We, as Yalies, should think hard about the egalitarian values that we promote and should consistently do so in the Greek system. Kappa and Sigma Nu should be considered the tip tier since they are the nicest and most egalitarian. Theta and Sig Ep should considered at the bottom due their being elitist and snobby.