I understand that - however, it does not inspire confidence that a system used to make payments could be used for a purpose not given explicit consent by the user. FWIW I am not so much concerned that this was on Android, but that it revels that NFC is vulnerable just like any form of communication.
You do realize you have to be less than about half an inch for the tag or payment device to connect? So let's say I wanna steal your info. I have to know where your phone is on your person, then hope there isn't too much clothing in the way, then figure out how to be that close to you for at least 2 seconds. Then, and only then, can the chips data be accessed. And most of that data has two layer encryption, like financial.
In other words, it's more likely you will get struck by lightening on a sunny day than have your nfc chip hacked.
By the way, I use NFC every day. I have 6 nfc discs that give my phone different commands depending if I am home, in the car or at work. You have to be pretty precise when you tap them to where the chip is on the phone. If someone has a phone in their pocket and the screen is facing outward, no crook could access the chip. Even if someone were to pit another phone up against your pocket. The inside components between the nfc chip and glass would prevent signal transmission.