A lot of smaller charities donation pages are readily abusable to "validate" card numbers, bruteforce CVV number, expiry, etc.
A few local charities that all had their sites running the same shit ended up getting absolutely hammered with charge back fees a while back, someone had been abusing their pages to check and crack card numbers to use.
Donation pages seem to be the easiest to abuse based on the data I've seen.
How do I know this?
Attempted fraud on a business card that is only used for those two places.