While walking through Philadelphia's 30th Street Station today -- http://en.wikipedia.org/wiki/30th_Street_Station -- I noticed a soda and water vending machine with the NFC logo. I thought, great, I'll try Apple Pay for the first time and get a $3.00 bottle of water. I hold my iPhone 6 Plus up to the reader, my card pops up (AMEX -- the only card my banks allow me to enter into Apple Pay so far), I hit touch ID and hear the little ding and see a check mark. The LCD screen tells me to choose my selection, (I chose D3 for a bottle of Aqua Fina water), it then says "authorizing" and then pops up with "card declined". Tried 4 more times and same thing. I'm guessing a $3.00 charge is unusual for AMEX and maybe that triggered a decline? Not sure. I now have a bunch of "unknown transactions" in Apple Pay related to these attempts. I assume nothing will be billed to me. Thoughts on why it didn't go through? I really don't feel like calling AMEX, just curious.