Why do employers ask for race on job applications?

It shouldn't be asked because surely the only reason you applied for the job is because you had the qualities they were asking for, and they didn't ask you for your ethincity in the advertisement at all.

But some may argue that it could possibly be useful for the company, say you were Chinese and your employer had a buisness in China they could ask you to be a translator for them.

But in my opinion it shouldn't be asked because it may make a person feel insecure about their race and ethnicity.