Simple.
1. The coder has no infrastructure costs. Many people work from their offices. Some have their own set up at home with a PC and a broadband Internet connection. Total initial cost of less than USD1000 and monthly charges of USD 10.
2. Many would have got experience in their current jobs and that come very handy for executing projects at RAC.
3. The conversion factor of USD to local currency is attractive.
For example top countries offering maximum coders
India - USD 1 = INR 46
Romania - USD1 = 2,77 RON
Pakistan USD1 = 60.48 PKR
Russia - USD1 = 26.77 RUB
Typically a good programmer in India gets USD 1500 - usd 2000 per month as salary and in RAC, he may be able to get as much working at his convenience. This does not include infrastructure costs.
4. Some new breed of entrepreneurs have come up to leverage RAC and they hire programmers at lower cost and bid in USD, thus making good profits.
However down side of the part is the programmers workign from their office and using that infrastructure and capitalizing on their official work experience. This is not ethical on the part of the programmers to make money personally at the cost of the current employer. I only request them to set up their own infrastructure at home and do it legally.
Anyway, thanks to RAC, there are far too many Indian programmers making good money.