I kissed a girl (closed mouth) in first grade all the time. On the hand. She liked it, so I kept doing it. Once the authorities got wind of it I got in trouble for it.

I just had a waaay too long convo with someone who just couldn't get around the fact that kissing is considered differently in some cultures. She thought it was just plain wrong for people to just it as a greeting. She thought it was just automatically sexual and therefore inappropraite.

The base metaphor is just an aside. Though there is the whole issue of what's considered sexual and how sexual. Some things are considered more advanced than others.