You act like it was his idea. It wasn't.
This was an alternative to a spending bill someone else introduced. I think it was an amendment to an existing Christmas for the Pentagon bill. He said, here's a different way to give the Military Industrial Complex a fat present. End these four things, a couple of which are whole bureaucracies, and give their budgets to the military. That way your pets get more but we don't have to raise the spending cap again.
That's why he offered them even more. He was lampooning these bastards. If you check, I feel sure you'll find that dollar amount is exactly the budgets of those four things he named. And since he probably didn't know how much Christmas these characters had in mind for the arms merchants in advance, he had to prepare and go with that number.