"A bold decision," Andy stated. "Very well, I'll go get you one." He got up from the seat and went to get a bottle of coca-cola from it. Figuring that too might be too sweet for the taste of his odd dinner-guests, and the bubbles would probably be a surprise too, he took a bottle with water too. He'd rather not have to get up again. 
It was odd though, that the man wouldn't know the name of a brand that was probably the most well-known around the world.

He paid for the drinks and returned to the table, placing the requested bottle next to his former patient's food. "Enjoy," he said, moving to eat a few of his own fries before they would be cold.