It's a pisstake of psychoanalysis. "Haha fuck you these dreams don't mean anything I just like dreaming!" It's also put to great use in the movie Batman & Robin where it's playing at the bike race Batgirl attends; the movie is telling you Batgirl considers motorbike racing fun for her, just like how Roisin considers dreaming fun for her in this song.
It's a pisstake of psychoanalysis. "Haha fuck you these dreams don't mean anything I just like dreaming!" It's also put to great use in the movie Batman & Robin where it's playing at the bike race Batgirl attends; the movie is telling you Batgirl considers motorbike racing fun for her, just like how Roisin considers dreaming fun for her in this song.