>>This is techno-paranoia looking for a cause.
>>During the past two years, my primary credit card has been cancelled and replaced 3 times because some hackers in who-knows-where got their digital hands on whatever >>they need to buy something weird with it.
>>What will they do if they get my phone that they're not doing already?

Yep, the hackers poll CC number combinations looking for a bite. And the banks are adept at comparing the attempt's geolocation to your card usage history to detect fraud.

But it's tough if the hacker is in the same locale as you. IOW if they steal your card and use it in service stations up and down the freeway until somebody notices, or hack your phone and empty your account using the same IP address you used this morning to pay for your coffee- then there's no cue for the bank. A popular trick is to copy a tourist's card and hammer it for 24 hours after they check out, because the bank won't detect anything wrong until the customer gets off the plane. The ability to hack a phone is far harder to manage than somebody in Burkina Faso getting a $1 hit on your CC so they can try to load thousands of $ onto it before anybody notices.