The radio station's night manager really Wolfman Jack having a conversation with Curt about about going back to college—and getting out into the world—encouraging the young man to enjoy life while he can. Also constantly offering Curt a Popsicle as a kind of sacred offering.
And offering to get Curt's message to the Wolfman so he can get it out there to the Girl in the T-Bird. Which he promptly does as Curt looks back and realizes what just happened.
What started off as an embarrassing prank on John - tricking him into babysitting the way-too-young Carol - ends up as a chaste romance as the two bond during the night's cruising. Although they both know in the end that the age difference between them would make it impossible for a real relationship to work.