I think you'll find you will be hard pushed to finds a developer to work for $6.66 an hour, even in the poorest countries.
In fact that is less than the minimum wage here in the UK by 50%, good luck.
Currently we have 4 developers from India, Russia and Ukraine working for 2 years with us...
This is the salary in this country's (depends on region in country) ...
As a business owner I totally understand that you would want to get the Job done as cheap as possible, but in the UK
if I was to pay my staff that amount I would be taken to court for exploitation, which can carry either a prison sentence,
a hefty fine or both, even UK Companies employing slave labour abroad are also being named and a shamed for there exploitation of people that are less fortunate and there businesses are losing money because of it, it is a shame but there will always be people desperate enough to work for low wages to just make ends meet.
But it's like you say it depends on where you are in the world and the standard of life they are living in, so it is all relevant to the cost of living at the end of the day.
You need to consider to stop buying 50% of goods you have in your house because its done by "slave labour" in China.
Thanks for link.