This is all the fault of the american banks who refuse to put the EMV chip on their cards. I live in Europe and my card has a chip. Using magnet stripe will fail at every terminal which is equipped with a chip reader as the use of the chip is mandatory when possible. Probably this is also the reason why the credit card data is abused in the states because you terminals don't have the chip reader and therefore will accept any cloned card, even copies of european cards which actually have a Chip.

The biggest bug in the code is that you insert to and subject into the mail header without any filtering. This is a source for many spam abuses, when spammers manage to control e.g. the subject and insert a newline into it, thus allowing them to insert own header lines and change the body.