Okay LookingForAJob your answer is good in a generic point of view, but let me give you some insights. First of all, I checked if Bahrain has laws against pay discrimination like most western countries in Europe and North America, and unfortunately it does not, so from a legal standpoint what they do is permitted, nevertheless, that does not necessarily make it neither ethical nor moral.
Telling me that foreigners must get paid more due to the fact that they require accommodation and tickets to go back home and family members coming over to live with them and all that, its is hypothetically sound until you see the numbers and statistics in pay difference. The median salary for a Bahraini ATCO in US dollars is $5000 a month (in Bahrain salary is calculated per month). Meanwhile, the median salary of a foreign ATCO in Bahrain is $15000 a month. That is a difference of $10000 a month! Now if someone thinks that accommodation and other expense costs $10000 a MONTH in Bahrain, they are totally absurd. Most expenses in Bahrain are equal for both foreigners and locals. Hell Bahrain as a country did not even have any taxes not until 2019. Before that it was a tax free country, and still to date there is no income tax, and it is not a very expensive country to live in, especially for someone that gets paid USD 180,000 a year!
This ain’t no rocket science, if you know how to count, you will realize the injustice in this.