This is an interesting point. I similarly don't think it's fair when I see Caucasians who are 1/8 or 1/16 Native American, or Hispanic or whatever list themselves as one of those minority groups to improve admissions chances by being classified as URM... as they look white and haven't faced the discrimination associated with such groups.
I feel bad for gay people, as they are by far the most discriminated minority, far more than any ethnic group.
Also being white doesn't mean you won't be discriminated against. For example, I served as the vice president of our college chapter of the NAACP this past semester. When we went to our state convention, one of our faculty members approached our adviser and President, saying that they "include too many whites" in the organization. Of course this tenured faculty member experience no repercussions whatsoever (I laugh when I think about the situation happening if it was a white woman complaining about too many "blacks" in an organization... I'm sure the end-result would've been the same /sarcasm/). I suppose that sort of discrimination is TOTALLY acceptable though, since its being done against a white male.
Also, I don't know if you found this out yet but there are poor white people out there too that get labeled as "white trash" all of the time. I live in a rural area where this is common. I guess they don't deserve any leg-up in the process though either, while a rich black/Mexican/insert-minority-group-here kid from the suburbs gets a "special status." The point here is not to take issue with the fact that minorities can claim URM status, its to take issue with what you seem to imply - that all minorities are discriminated against and whites are never discriminated against.
Also, there are "white" people with accents... like many of my relatives who come from the countryside in Ireland. Or my neighbors, who are from Russia who barely speak any English.
The point is, discrimination is about more than just the color of your skin.
Your statement suggests white people don't experience any discrimination when in fact you are incorrect. I think my examples outline that for you.
And I don't want to get into a URM argument with anyone, because I don't care. I'm simply addressing his line about white people not experiencing any discrimination and nothing further or less.
AND also... the whole URM thing doesn't have anything to do with discrimination. As ChemEngMD has already said, it was put in place so that different racial/ethinic groups get more doctors in their community who are of that racial/ethnic group. Its not equivalent to affirmative action. And so by discussing discrimination you are discussing a completely different topic that has nothing to do with URM.