As a non-native speaker, I would never have guessed that this mistake was a thing before I read it on the web.

Since it makes no grammatical sense, I can guess that it can only be seen in the writing of native speakers because they have learned the language through oral communication, while most non-native are exposed to written English from the very beginning of their learning. I also guess the accent may influence the appearance of this error, and thus I am wondering, where are these people from?

Is it more of an American English thing? More British English? Something else?