Roku also allows the app developer to determine where the app runs. So, if you're in a place that the app doesn't work, that's because the app developers (Disney and Amazon, in your instance) have decided to not support the Roku app in those regions.
As for why? Well, Roku itself is not supported there. If you have a Roku there, it was imported. Roku wasn't sold through an authorized seller in that region.
Many app developers will not support their Roku app in regions where Roku itself is not supported. Disney and Amazon won't support their apps in such regions. Many others won't either. But some will. Netflix, for example, works there on Roku because Netflix chose to support their app there.
If you want the apps to work there, it's up to Disney and Amazon to make that call. Roku isn't the one stopping them from working.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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