There's a magician/illusionist involved here, so we know it's a trick and it's pretty easy to work out how it's done. Like most magic, it's based on false assumptions. The trick works and impresses because the illusionist knows the assumptions we'll make and ensures that we make them.
Efective marketing should also be based on knowing the assumptions your customers will make. Advertising agencies call these insights. Sometimes they are, sometimes they aren't. But, I'm not sure the analogy should be taken all the way. Here, the patsy knows he's been fooled, yet doesn't mind because he went in expecting that to happen.
In some categories, specifically those with a fashion basis, customers are relatively happy to be "tricked". Fashion, however, is fleeting. If your product/service is less transient, I think it's probably acceptable to exploit customer assumptions in pursuit of giving them greater satisfaction, but I don't think that justifies deceiving them. That's where marketing gets its bad name. Any thoughts?