For some reason some seedbanks will not accept prepaid credit cards. I think the reason is with a regular credit card the funds are guaranteed and with a prepaid credit card they are not. With a prepaid credit card it is basically an electronic check. They have to wait to see if the payment clears before they can ship because if they ship and then the payment is rejected because the balance on the prepaid card is to low they lost out plus they are still charged the same percentage by the credit card company, which ranges a good bit depending on whose credit card processing system they use, so they not only lose out on the sale and shipment but have to pay on top of it. So with a regular credit card they have security of payment but they do not with prepaid credit cards.
Supposedly when the transactions are made electronic verification of the funds is verified, so they would know the funds existed, but if after the initial transaction is made the prepaid credit card is used again if that transaction or transactions are processed first/faster, as in someone in the U.S. using their card and a local business processing their transaction(s) faster than an overseas company might be able to do or if the company say does it only once a day, then the funds that appeared to be available when the transaction was made and the sale approved would no longer be there and without open credit to cover the transaction or the guarantee of payment if the business ships they may get stiffed and then still have to pay the processing fee on top of it.
Also, and I may be wrong about this because I never read it from a credible source and have only been told it by people I know who are in business, who I do trust but understand that it may not be the same with every credit card processing business so it may be the case with them and not in every case, but I have been told that there is a higher processing fee/percentage for prepaid credit cards than regular credit cards so that cuts into a businesses profit and they tend to not care for that much so there is less incentive for them to accept prepaid credit cards.
So it might be wise to email any seedbank you may wish to deal with and ask it they accept prepaid credit cards or not. I have to believe that some do but I have seen some where when you click on payment options under the credit card payment information is says they do not accept prepaid credit cards.
As for security of using credit cards for payment of beans any seedbank that I have ever checked with about their billing, and some or most will tell you under their payment, billing and shipping information, is that they do not use names like The Attitude Seedbank on their transactions so credit card statements and debit card statements will not say The Attitude Seedbank and will instead say Attitude Gifts. I do not know what Reefermans seedbank uses now but in the past it was some generic name with novelties after it like Emporium Novelties or something.
So it is not a blatant red flag waved in the air if someone uses a credit card or a debit card.
I would still suggest using a money order, an international one in most cases since if someone lives in a different nation that is what would be required, but again paying by credit card or debit card is not the major red flag most people believe it to be, at least not in all cases and if someone is going to use a credit card or debit card they should be intelligent enough to search the seedbanks website for billing information and if they do not find the information email them and ask.