I've driven EVs since 2013 across several states and I've never once encountered a functioning public charging station in the US that has a credit card reader and does not require payment and/or access via an app. I'm all in favor of it, and I understand they technically exist, but perhaps your specific locality requires that? It's in no way my experience.
Even aside from that, many charging networks _do_ require "membership", "running the app", and often even require a pre-established balance on the account for the most convenient charging process.
It seems Walmart is also planning to follow this strategy, which is the point of the original objection.
Add to tourism gatekeeping checklist - a verified US phone number or local bank account (popular in Europe). Oh and the "app is not available in your country".
It doesn't. Almost all DC fast charging I've done has been plug and charge or with a normal credit card terminal.
Meanwhile when I buy gas at QT or Sam's Club I pay through an app.