Do companies in the Middle East realise that it's bad PR to specify preferred nationalities to jobs they post?

Unfortunately, this is a very common mistake many companies in the middle east have been fallen in. At the time qualifications must be the bedrock of the success of any organization, lots of companies use margin standards for choosing their workers. 

No wonder, thousands of middle eastern geniuses prefer the idea of immigrating abroad, rather than waste their passion and their willingness to learn in countries do not appreciate.

In my opinion, I believe continuing in this way, will lead to nothing but losing good qualifications to the behalf of western countries.