100% staged.
First, he's not allowed to eat McDonald's by his doctor, and he probably doesn't even like it, never has. That's always been bullshit. There's a White House chef, at least one, on staff in the kitchen.
Second, there's no way the delivery would be brought up to the door by the driver, it would be dropped off at the gate, and taken by staff from there.
Finally, the idea that he would answer random questions from a stranger is laughable.