I had no idea that there was symbolism for kissing without kissing associated with sharing an apple.
Personally, seeing it in Melody, I thought: Yuck, I wouldn’t share an apple and take overlapping bites like that. I also thought: That’s so cute. I also thought: Well, if you’re in love and you’d kiss, how is it any different, risking the shared germs?
So it makes sense.
I just assumed the apple was included, besides as a useful visual, in reference to the lyrics of First of May. I assumed it was additionally included as a reference to growing up, becoming less innocent, learning to love, drawing on the “apple” reference from the bible in a sense.