I might be paranoid, but I like that my bankcards are in a metal case (I got it because it's water/dustproof, but I like the bonus) and I like that Wallet only activates the rfid for a second, then I'm no longer broadcasting.

Having cards on back of phone triggers the phones NFC reader for the cards ship, causing apps to launch or other messages to appear on screen.

Tape to pay, that is.