They don't represent just any cause, they're purpose is to protect civil liberties (e.g. free speech and the freedom to use words like "white" in organization names). They are the defenders of the Bill of Rights.
Yes, the ACLU supported the KKKs right to march: http://www.aclu.org/FreeSpeech/FreeS...m?ID=8640&c=42. Many scholarships are given by private organizations, if such a private organization wished to give out their scholarship only to caucasians, homosexuals, blacks, they can and they can also name themselves "The White-Scholarship Only Fund" or whatever the fuck they want.
I did not cuss at you, I said "whatever the fuck" which I say often, like in the above sentence.

Thank you and good night.