Vintage drive-in ads for soda pop, accompanied by the catchy song "Cold Drinks" by Weird Paul. The Song can be purchased here:
https://weirdpaul.bandcamp.com/track/cold-drinks-2.
A live version of the song is performed during the end credits and can be viewed here: 
Song used with permission.
▶️ Watch on DTube ▶️ Watch Source (IPFS)