Also unethical is not automatically given them a refund, and then verbally trying to humiliate them over their choice of reading when they request one.
(warning: strong language)
I'd love to know if someone's actually run a scam like that at some point. Seems like a clever hack, at least it would be before the days of ubiquitous credit cards and online banking.
Not sure if it was original when included in the script or not.