Why is the slogan Denham's Dandy Dental Dentifrice repeated over and over in Fahrenheit 451?

I think the point of the subtle commercials is to show how easily the general population is swayed by advertising. The entire story is about the influence of advertising and commercial exploitation can be on the entire population. The author was trying to get people to see what could/was happening to their freedom, but, unfortunately, he did not reach an understanding audience.