That Mysterious Background Extra from GREASE (1978)

I've always been curious about a lonely background extra from Grease (1978). A haunted young man who briefly appears 2 minutes and 24 seconds into the song Summer Nights, seated behind the Pink Ladies and gazing wistfully into the middle distance. Who is he? Why is he?

Here, we see Olivia Newton-John begin to lament the end of summer, in turn causing this lone, random rooster in a henhouse to reflect on his own experiences of love and loss. The universe of Grease is nothing if not totally segregated, so why is he hanging out with these broads?

He seems lonely. I wonder what he's thinking about. Why is he wearing an apron?

Attempts to locate this guy have amounted to zilch, so I've compiled a handy list of plausible theories to explain this man's rather awkward presence.

1. He's a cafeteria worker on a smoke break. That would explain the apron. For some reason, everyone in this seemingly Californian school is Italian. Maybe he's fresh off the boat and pining for the Old Country.
2. He's a rare, 1970's, on-screen portrayal of a lonely gay teen. Director Randal Kleiser is openly gay, so perhaps this was an early shout-out to, you know, boys who don't dance and sing on the bleachers with the other boys.
3. He's Christopher Moltisanti from The Sopranos. This would render Grease, in effect, a prequel to the Emmy winning HBO series. Some might say that's a stretch, but I think Ruthless People (1986) is a sequel to The Rose (1979)—Bette Midler's self-destructive rockstar character faked her death. Also, if you believe in time travel, Jumpin' Jack Flash (1986) is clearly a sequel to The Color Purple (1985).
4. He's a ghost, hell-bent on bloody revenge. Everyone remembers the Ghost Kid from Three Men and a Baby (1987). Well, I'd like to see the know-it-alls at Snopes prove that this man isn't, in fact, the vengeful spirit of a dead dishwasher who's been haunting Venice High School ever since he was sucked into and drowned by his own Maytag. Rumor has it, Olivia Newton-John wasn't directed to warm her arms whilst singing, "It turned colder / That's where it ends." She just felt an unmistakably malevolent chill emanating from the other picnic table.
5. It's some caterer or make-up guy who was told—at the last minute—to jump in the shot because the background looked "spartan."

If you have any equally logical theories as to who this background extra is, or you are, in fact, the background extra himself, leave a comment.