This is not a forum for hackers. So I will not explain how it will be possible to hack your info using this method of payment. All I will say to those who fill safe using this method do not be surprise when this happens, if Apple even own up to breaches. I am aware of methods how hackers can get your info from this. Whether this is reasons why these stores decide to stop offering this form of payment to customers I do not know. I CAN SAY this is not as secure as they (Apple) would have customers to believe.
Thanks for NOT explaining it then.