As you agreed yourself the pay scale difference/gap between a Local & expatriates is too high. and they can not work in the private sector since working environment, work load, work pressure, facilities provided to employee are more less than the public sector. so a local can not work under such environment, and other hand they can get a good job in a public sectors with high pay, good working environment,relax in the work etc etc,.
I 200 % Agree With VANMOST comment.
As you agreed yourself the pay scale difference/gap between a Local & expatriates is too high. and they can not work in the private sector since working environment, work load, work pressure, facilities provided to employee are more less than the public sector. so a local can not work under such environment, and other hand they can get a good job in a public sectors with high pay, good working environment,relax in the work etc etc,.