Going to Camp David is one of the cheapest and least disruptive things he can do. Camp David has a permanent staff and all the communications gear needed. They get there by helicopter from the WH grounds.
No big planes; no 30 car motorcades; and no SS security checks. And best of all, us ordinary schlubs don't have to cool our heels in traffic waiting for the procession to pass.
What is wrong with him staying at the WH and saving helicopter fuel? One night wouldn’t hurt him since he returned today.
It wasn’t that cheap. Did you see the gaggle of relatives accompanying him? It was yet another one of his “extended family vacations on the US taxpayers dollar” extravaganzas.