CC companies like you to try and resolve it with the merchant first, if possible. Obviously if it's overt fraud (e.g. charge without your consent) then it's not the case, but if the merchant can prove you authorized the transaction (even if you regretted it later), and you claim it's unauthorized then you will be committing fraud. It's probably not something you can be prosecuted for, but the CC company wouldn't like you trying to defraud them too much. OTOH, if you contacted the merchant and tried to cancel and they didn't respond or refused, then the CC company would likely be on your side. So the merchant that is trying to look like legit business would rather cancel when asked. It's not about being nice, but about following the rules. The rules are in your favor, but if you are the one breaking them (e.g. by pretending the transaction is not authorized while it was) then it may turn against you.