I have been thinking, and considering how pro-faunus Ruby and Yang are (specially after they confirmed that Roman isnt unusually racist, and his racism is sadly common), I think that particular aspect of how accepting of Faunus they are comes from their family. Maybe Qrow (and possibly Taiyang/Raven/Summer too) where pro-Faunus, or even activists, which could explain his apparent beef with Winter SCHENEE.