Elon does some quirky things, but missing an opportunity to show off the X to that big of an audience, and doing a wink to his previous appearance on the Late Show the S prototype, while having a host who is interested in the car (unlike Dave)... But nah, let's just have Elon fly cross-country to chat with Stephen about rockets and South Africa or something. Right-oh.
David Letterman had/has a Roadster, I believe. That why he complains about the height of the car. He is tall and the Roadster is low to the ground and hard for him to get into.