Okay let me tell you why they WON'T get any better salaries ,even thought they can get it.
Because most of them will just grab the salaries after couple of years and get back to where they came from.
Let's analyse that again, what would you call it ?
I mean before they even come here they always kept in mind that they WILL get back.
I mean India has a very high GDP, so instead of you 1 BILLION people fighting the people who owns all the money in your country, you (hundreds of thousands of you), go to someone else's country with a purpose of GETTING back.
I mean many are living in Qatar for long years, have they ever thought of helping the community (of course not judging everybody).

So let's follow your logic, give them a double or triple raise, in 5 years the country will go empty , and thank you O'grateful wise people!