In full honesty, I think SpiceJet wills survive just from the pay to fly locals. They charge their cadet pilots approximately 150,000 USD for training from beginning to 737 rating. And they have no shortage of those, they actually cant accept everyone who applies since they fill up every time in batches of 30.
From the expats perspective its just the Indian mentality of screwing you over once you've done the job you were required to do for them. What can you do once you've left the country ? Nothing. So they just drag you along till you give up on trying to get your pay.