You must not have used Pay. Super simple. Super fast. I would never go back and hate that more retailers don't support it here in the U.S. (yes I'm looking at you Target and Walmart).
Meh. Walmart is causing problems over here too. Their UK branch which you may or may not know is called 'ASDA' are also refusing contactless payments and Apple Pay purely because Walmart doesn't support it in the US. Can't really understand the logic of a company that believes staying in the past is the right business move.