There seems to be this recurring idea that no one ever looks at the Federal Budget and so lots of waste, fraud and abuse must be in it. Nothing could be further from the truth.
Every President, Senator and House Representative has staffers going through the budget on a regular basis looking for things to cut. Not because they care about the deficit (anyone in DC who actually cares about the deficit is a sucker, but that's a whole other story), but because they want to free up money for their own projects. Anything in the budget that does not have political support from somebody is quickly cannibalized for resources. One man's "waste, fraud and abuse" is another man's "vital constituent interest".
In theory, Congress has the power of the purse and decides amongst the People's Representatives where the money should go. Everyone gets a say in what should be spent where.
That is... not what is happening now.