If you ask me this billboard and another recent billboard for McDonald's coffee place too much value on a customer’s income. This billboard is not only a put down to people in the city of Flint, it also implies that a person must have monetary wealth in order to have good taste.
At any rate, the pragmatic aspect of this billboard is what first jumped out at me. It is well known in the study of pragmatics that the context in which communication occurs plays an important role in the listener's ability to interpret the speaker's intended meaning. In this case the communication is between writer and reader. The reason I see this as a pragmatics fail is because the context of this communication is its location and I don't believe that the writer took the context into consideration. What I am referring to is the fact that this billboard is on an interstate highway that is travelled by people from many different cities and states. Unless the reader of the billboard is very familiar with the zones that zip codes cover and the income level of the people in those zones, the billboard doesn't really communicate to the reader the writer's intended semantic implication.