Discriminatory Questions or Necessity?

I was just speaking with a friend who informed me that on a recent application to an educational program, he was asked about mental illness. Such questions as "problems with neurosis", "addiction", and "hospitalization" was what I gathered. Now, correct me if I'm wrong, but if you can't ask a person about his/her religious position or sexual orientation due to possible discrimination then it seems equally as discriminative to ask about any kind of illness be it mental or physical. We all get illness, the flu, diabetes, ashthma, arthritis, depression, fibromyalgia, and the list goes on and on. If employers/educational institutions are going to make decisions based on illness of any kind then none of us would be employed or going to school!! If, as another friend pointed out, it might have to do with insurance policies then if would seem more appropriate to ask that question only AFTER the individual has been hired or accepted. Illness may temporarily affect a person's ability to perform his or her job duties, but only temporarily and infrequently. If not infrequently but over a sustained period of time then that person has the right to go off on sick leave and his/her right to return to work when the illness has been treated is protected by law in most situations. The very fact that anyone would ask any potential employee or student about mental illness only reinforces the fact that the stigma associated with mental illness is that those afflicted are unreliable or incompetent. This, to me, is no different then different washrooms for different races fifty years ago or the gay and lesbian individuals being denied work or bullied out of communities at that time as well! This is the 21st century! We thought we had the whole discrimination and prejudice thing under control, right?! What's your view?