The wording and the visual images from the image contribute to the use of satire in this advertisement. The diction (words) appears secondary to the picture of two very large men and the intention is clearly to draw attention to the people before concentrating on the actual phrasing. Once the actual wording does get your attention however, it builds to a climax and the excitement intensifies through the repetition of "food."
Anyone who is obese will obviously be drawn to the word "food" and in building up towards the ultimate answer, to what will "change your life," over-charged words are used - trend, revolution - and, who wants to "miss out", especially if you are obese and there is talk of food ? It is also obvious that these men do need to change their lives - or at least their lifestyles.
The humor is scornful and berating but the use is subtle. The speaker looks like a caring, wise man who would certainly not tell a lie! The verbal irony becomes apparent when we get to the "Mc Flurry. " Even though it is a short written passage, there is a hint of rheutoric as the kindly, older gentleman attempts to persuade the, apparently easily - convinced seated men, that even a Mc Flurry will change their lives.
It is more likely that adding McFlurrys to these gentlemen's diets will end rather than change their lives! Hence, the advertisers are being mocked for their methods of inducing customers. When compared, their techniques are actually similar if not quite so obvious. Advertisers pride themselves on their powers of persuasion. Do they want to contribute to obesity? Is advertising income more important than consumers who may actually benefit from sound advertising practices?