I can’t speak for America but in the U.K. there have been terminals that do this that small independent businesses have used for years. They connect to your phone too and work with both Android and iOS. You see taxis, street food sellers and all sorts using them. They also cheap and yet still look a hell of a lot more professional than this thing does.
It is the same in the states with Square (among others), but the ease of “I have to do nothing” is nonetheless extremely alluring to the most adhoc of businesses.
They're fairly common in the U.S., as far as 2015 that I remember, except they're often flaky, rely on Bluetooth and have their own battery, which many means merchants who don't use them that often would switch them off to save the battery. And with your iPhone, it's likely you have it charged and turned on at all times.
Sorry, by ”this thing”, do you mean an iPhone? That it looks less professional to use a phone than a dedicated card reader? I can see it, I was just genuinely a little thrown by the wording.
Sorry yeah. I don’t know why I shouldn’t trust tapping on someone’s iPhone but it doesn’t scream “professional shop” in the same way that those card readers do. Even though those card readers are very cheap and ostensibly work the same, they just feel more “professional”.
https://merchantmachine.co.uk/contactless/
Note that some of these even have chip and pin readers for those without contactless.