Each Congressional representative is hired by a particular constituency
to be their man or woman in Washington. If a politician is from Vermont, his
job is to look out for Vermonters. The way Congress works, Senators and
Representatives negotiate until everyone has a deal they can brag about
before the next election. Each negotiates hard, to get reelected and incidentally
to look after the interests of the people back home. This system gives each voter an
advocate in Washington.
Yes, I believe "pork", or specific beneficial spending for their home states or home districts is completely justified. As a representative of their constituency, they have an obligation to at least attempt to make decisions that will benefit their communities. Because representatives from all parts of the nation are present, it seems that "pork" spending for all parts of the nation would actually be more representative than not.