Also, anytime you want to order a drink in one of the onboard establishments, they would have to bring a portable reader to your location. I think they figure such a major investment in equipment and training is not needed.
However, it would be nice if they could allow you securely add the KTTW cards for your family to the
DCL app on your smartphone. It still would not work for transactions unless they updated all equipment to work with NFC or some other protocol (and an open NFC API from Apple for iOS devices), but that might be a more likely scenario in the future.