For a reason... Go read the Constitution. DC is a Federal District (seat of our national government) and as such is supposed to be neutral, non-political, therefore no Senators and Reps
Plus DC gets tons of Federal money, lots more than they pay in taxes
Yes, but that applies to the city as a whole...there is still the issue of individuals not being properly represented.
I would be fine with getting a pass on my Federal taxes, though :)