Maybe he should read The Critique of pure Reason first and then Shakespeare's Hamlet: " To buy or not to buy ...".1. If you do, you risk them fixing their mistake and potentially raising the price
2. Thats a philosophical question. According to Kant’s Categorical Imperative, the right thing to do would probably be to inform the business, as you would hope a customer would do so if the situations were reversed. There’s a certain degree of dishonesty here. But, on the other hand, there’s certain expectations of a business exchange, including that the consumer will try to get the best for them as will the seller. So, to answer your question, I dont see this as ethically wrong, but it’s also not something to be particularly proud of. Im sure most consumers would just gloat about screwing over GC
3. I think they can cancel the order if they realize their mistake.
Btw, you got the perfect nick to give valuable advice, good one, dude!