I think I read about this rule here on HN and have been following it since a couple of years. The funny thing is, banks do scammer like things so often. I had a yearly subscription that tried to renew and they tried to charge me first for 0, and bank rejected it. 2 hours later I get a call from a weird number from my city (when my bank is in another city and all official numbers are from there) from apparently the fraud department of another bank that now handles fraud prevention from my bank. I refused to give them any info, told them I will call the bank back and just called the number on my card, which is the default support number for my bank and sorted everything out in 5 minutes.