Why the inconsistencies of how Vegeta was destroyed?

In the early episodes of DBZ, King Kai tells the story of what happened to the planet Vegeta. It's guardian was a good man who became disillusioned with what the Saiyans had become and called down a storm of meteors to destroy the planet. That's the story King Kai tells Goku. However, during the Ginyu Saga and Frieza saga, it's revealed that Frieza in fact destroyed the planet. Did King Kai not know this(I doubt it since he seems fully aware of who Frieza is and what he's done in the past)? Or was he sparing Goku that information so that Goku wouldn't feel pity on the Saiyans he was about to battle?