Cars and Commercials

Have you ever noticed that some products appear more in commercials than others? I definitely have, and three stand out the most to me. The one that appears most often are car commercials. There is always the "Year's biggest Sale!" every weekend or nondescript holiday, which doesn't make sense because that sale can only occur once per year. Then comes cell/phone/TV/internet service providers with each of them seemingly using a different set of facts about each other's quality and price of services. Finally, I see a lot of car insurance commercials. Each of them claims that if you switch from a competitor's policy, you will save a few hundred dollars a year. I guess I will just keep switching from one company to the next until I get a plan for zero dollars a year.

What other types of commercials appear frequently? Do they all make sense or are they repetitive?