Can you imagine it? I'm pretty sure it had to be something like this...
However, Wendy's is not the only firm which employs these methods in order to persuade the customer. Let's see that most of the companies (fast food restaurants in this case) use what is called "Deceptive Advertising":
According to the FTC (Federal Trade Commission) defines "deceptive advertising" as a representation, omission, act or practice that is likely to mislead consumers acting reasonably under the circumstances.
How the customers respond to this?
In order to answer this question I found an interesting article about the consequences of deceptive (or false) advertising in our brains: http://www.sciencedaily.com/releases/2012/02/120228102011.htm