Or, that was the old ploy of the Park Service, whenever Congress wanted the Park Service to cut back. i.e. Congress would cut the budget of the Park Service and tell the Park Service to cut its less important parks, which the Park Service did by first defining the least important park as being in DC. We have to remember before Disney World opened up in the early 1970s, DC was the #1 tourist destination on the nation. By closing down the DC Memorials, tourist would find them close and then go to their Congressman and complain. Congress would then allocate more money for the Park Service.
Now, the Park Service was the most overt practitioner of this art (and congress "solved" the practice of the Park Service, but making a separate line for the Washington and Lincoln Memorials, thus the Park Service can no longer close them down when Congress cut the Park Service's Budget) the other branches of Government were worse. In the 1980s for example The Air Force, when told to cut expenses would say it would ground all of the A-10 attack planes, knowing the Army would fight to get them back for the Army was more dependent in the A-10 then the Air Force was. Another example was the Army was told to close down bases, would put up Azores base for the first base to Close, the Air Force which did the Security around the base would agree, both knowing the Navy, which flies the planes out of the Azores would fight to keep open the port (run by the Army) and the Security for the base (run by the Air Force). The Navy and Marines are not above such fight, in the 1990s the Marines ask to be assigned new missions so it could expand, and justified the growth on the ground the Marines could do it for it was ship based, and all that was needed was to transfer Tanks from the Army to the Marines.
I fully believe such items are in the proposed budget, items that the various parts of the executive branch know Congress will add or expand on its own. Other parts are in the budget to give Congress something to cut, so Congress can show it has cut somethings.
Remember it is Congress that actually decides the budget, all the proposed budget is an offer by the President what he thinks the budget should be but it is nothing but the base Congress will use to set the actual budget. This is the start of the Fight not the end point.