Freberg had made a successful career in advertising, and did for many years after this, as well. But because of that, he knew the inside of the profession, and made a biting satire on it all for the impact of advertising at Christmas. The recording was very controversial at the time, odd given the point of it all. Though it's understandable why radio stations might not want to offend their sponsors.
Stan Freberg had no such compunction.