In the above set of commercials, a serious, well-dressed man asks "Could switching to Geico really save you 15% or more on car insurance?" followed by a comedic rhetorical question which the adjoining video clip answers as "yes." The initial assertion of each rhetorical question is an example of a non-sequitur and faulty analogy. None of the rhetorical questions have anything to do with whether a customer could truly save 15% or more on car insurance, but the man asks each question with an icy seriousness that might temporarily trick the viewer into believing they might be related. In the mind of the audience, whether or not Geico's claim is true is reliant upon the answer to the ridiculous follow up question, to which the answer is inevitably yes. This could also partially be a straw man argument, because the man is misrepresenting the possibility that Geico's claim is false by saying its only false if the answer to the rhetorical question is false, which it is not.
Generally, however, the people who watch these commercials are not convinced to buy car insurance because they are guaranteed to save 15% because "a bird in the hand is worth two in the bush." They are convinced because the absurdity of the commercial is funny, and that humor draws them to remember the claim of being able to save 15% or more on car insurance.