The examples you cite are not comparable to the caste system. The caste system explicitly implies inherent inferiority/superiority in one human being over another.
- You should ask KKK/Neo Nazis if they consider Blacks inferior or superior?
- You should ask Chinese if they consider the mixed race Black singer (from the Chinese version of American Idol) inferior?
- Some Muslims consider non-muslims Kafir.
- Shia and Sunni consider each other inferior.
- Some muslim sects in Pakistan, and elsewhere, are considered non-muslims.
- Jews consider Palestinians, and vice versa, inferior.
And so on and so forth...
So, yes, those examples do apply.
My point is that this is one more manifestation of an inherent feature of human behavior, to consider similar people to be better than dissimilar people. Societies that become prosperous and educated can counteract this urge to some extent, but I haven't seen any society that really stamps it out.