why 'Caucasian' or "white" is still supplied on forms and surveys

If a group is culturally assumed to be inferior for whatever reason eventually the term used to refer to that group will be taken as a slur. It will be replaced by some other term by people who don't want to be perceived as considering that group as inferior. Eventually the new term will be considered a slur and another new term will be coined to replace the old. What is needed is to stop considering the group inferior. Since Caucasians or whites are the culture that's doing the considering there is no need to replace the term referring to them.