They should be honored to attend on the arm of a Marine.
Oh, okay, I'll play along:
"Military service is so honorably badass that the beautiful and powerful are clamoring to be on the arm of any Private Snuffy simply to pay tribute to their service. The stars are virtually beating a path to the barracks in search of a date. I don't know why I didn't ask Scarlett Johansson to one of my balls. I am sure she would have said yes, and even my wife wouldn't have faulted me for that move!"
But back in the real world: The guy scored a date with one of the most beautiful actresses in Hollywood. She could have easily blown him off with some glib statement or signed picture or feigned excuse, but instead she is going with him.
That's a classy move on her part and "Scotty" is a lucky SOB.
"Fortune favors the bold."