I'm an American android user and I'm confused too. At least in my area, contactless is pretty ubiquitous now. (I accept adoption is slower, but it's getting there)
Sure Apple Pay seemed to come to a lot of terminals first, but NFC Google wallet or whatever it is the phone does automatically I've only seen fail at certain terminals. In that rare case, usually someone behind me with Apple Pay often also fails, so I'd be more likely to attribute it to a system glitch rather than lack of support.