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How can I scam someone? I am under the impression that I give my card details, then my payment is processed and I am given my bitcoin. I don't see how I could rip someone off. Though I am new to all this.
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Maybe it's news to you, but credit cards can be and tend to be stolen. There's a whole criminal business dealing in stolen credit cards (
https://en.wikipedia.org/wiki/Carding_(fraud)). If the real owner of the card complains and is refunded, the merchant who accepted the card is the one who takes the loss. So especially with higher-valued purchases that cannot be easily repossessed, the seller should check the customer's id thoroughly to avoid being defrauded.
Onkel Paul