Again, while still unfair, if you'd want to offer discounts to some regions, I wouldn't personally take a stand against it. But if you claim to do it for such reasons, you should strive to apply those discounts for all poorer regions, not "forget" about those that actually are the poorest, like I was saying about offering discounts to Latin America or China or the former CIS region but not to (most of) Africa or Southeast or Central Asia...
But what I really do take a stand against and call rotten is if you'd (also) want to apply the typical 1 USD (for US price) = 1 EUR (for EU price, even for non-Euro countries) rate, or similar price hikes for UK or AU/NZ, because there's no way to claim that the purchasing power there is far greater than that of the US (except in Luxembourg), and in most of the EU it's lower.
Edit: So an acceptable regional pricing scheme would involve a flat price for the wealthy countries, no possibility for regional pricing between them, and let's say we can define wealthy as above double the world average taken by purchasing power parity, which actually gets us at the moment to a round number of 30 countries, down to NZ, as per https://www.theglobaleconomy.com/rankings/gdp_per_capita_ppp/ And for any other countries you could set the price as a percentage of that base/maximum one, which percentage must not exceed 100%, and any price you set for one country automatically becomes the maximum one for those ranked below it. That should fully cover the cases you use to argue in favor of it, correct?
But it's not how typically it's done...