Sorry but I can't any keyboard on the trezor to type the amount of money you want to send nor do I see any wireless capability. Trezor is only for techie people not the average joe.
From my personal experience (if you don't consider Wifi direct devices, which are not really mainstream), it's easier to connect a USB device to a computer/tablet than to configure a wireless/contactless connection.
IMHO it's also more convenient for the average joe to recheck something on a second screen than to type an amount (or an address, not considering the payment protocol) on a tiny keyboard.