FaceTime blocked by Apple

Does a person has the right of purchasing apple products from anywhere in the world and use all the services equally with the rest?

If yes, why i am not able to use FaceTime app on an iPhone purchased from UAE while living in a country that FaceTime is not banned/blocked/locked.

Requesting the community to ask apple not to ban or block an apple service by model number, but rather by region or carrier. As if one is shifting to a different region and carrier, he or she should be able to use all the services.

Thanks,