Your response just begs the question: “Why did Warren Beatty get the wrong card?”
The envelopes had typography problems as well. In the previous year, the envelopes were red letters on a gold background. This year, they were gold letters on a red background, much harder to read.
Yes, someone handed Warren Beatty the wrong envelope. But for something that’s this important, you need layers of redundancy, and getting the message right on the card (and making the writing on the envelopes legible) is just as important as getting the right card in the right hands.