 By the late 1920s, radio had reached critical mass and saturated the market, necessitating a change in business model.The sponsored musical feature soon became the most popular program format.Most early radio sponsorship came in the form of selling the naming rights to the program, as evidenced by such programs as "The A&P Gypsies", "Champion Spark Plug Hour", "The Clicquot Club Eskimos", and "King Biscuit Time"; commercials, as they are known in the modern era, were still relatively uncommon and considered intrusive.