What do do with a windfall

King's post about what people have done with stimulus checks (2008 and prior) brings up the question of responsibility in finances. When citizens get a windfall (say the 2001 or 2008 "stimulus" checks), they overwhelmingly saved it--or at least used it to pay down debt. When government gets a windfall, on the other hand.....

....why is it that we so consistently send our most fiscally irresponsible neighbors to the legislatures of our nation?