Did you know that Prince's Purple Rain was actually about the end of the world? Probably not. If the late singer himself hadn't elaborated on the song's subjects people would probably still be tossing theories out and seeing if they stick.
So that was one instance where the mystery was solved, but there have been many other songs with lingering questions. Songs that may really grab you, but when you have a chance to actually pay attention to the lyrics, perhaps when you're not in your car in a hurry to get somewhere, that you realize something - they make no rational sense in any way, shape or form.
In some cases, this is done on purpose. For whatever reason, the artist has decided to just mess with the listening audience. Other times it can be something like references to something profound in an odd, coded message.
Whether you love this type of music, have an intense dislike for it or something somewhere in between, theses kinds of songs have been around for a long time and likely will be for a long time to come.