You’re right, the White House has cooks. And if the President had said, “We could have had the White House cooks whip you up some salads.”, then he would be throwing around his class privilege. If he had offered to personally make them some salads, he would have been overbearing for taking jobs away from the White House cooks (and it would have been pointed out that the White House “help” has been historically predominantly Black (which history would be somehow Trump’s fault)).
Not during a shutdown. Trump paid for the lunch himself.