The reason in many cases has nothing to do with racism. To me personally, it’s a strategic decision. Here’s why:
We are working on a startup and from time to time we need some scripts from Codecanyon not to write everything from scratch.
When I see a script that is a good fit, first thing I do is to check how the author responds to comments, as getting quick and quality support if something goes wrong or just doesn’t work is critical to us.
When I see an author cannot communicate his thoughts in plain English or even worse - does not understand the question and gives totally different answers, that’s a clear red flag to me, as eventually it converts to lost time and money which a startup simply cannot afford.
Thus, speaking from a buyer’s perspective, I believe that’s the main reason one would not buy products from an author regardless of the country of residence or the nationality.