Can anyone explain Mimi on the Beach to me?

I recently discovered Jane Siberry and have been checking out a couple of her albums. I was just wondering if anyone knew what she is trying to say with this particular song. She seems to have disdain for the young adults on the beach, but I can't work out how she feels towards Mimi. What is Mimi's relationship to the other young adults on the beach? Why do they make me feel uneasy (and is that what she's trying to achieve)? And is this a made-up story or based on real life? Sorry for so many questions, but I'm really curious and can't find any information out there.