Before you jump to conclusions from this graph [1] about India, keep in mind that for most families, making $50k a year is a glory. You can live luxuriously, drive "high-end" car(s), but a moderately-large house in a couple years etc. You get the idea. I always hate it when they compare economies in $ for everyone.
I don't think living in India makes consumer electronics, cars, worldwide travel, world class education, clean neighborhoods, reliable electricity, good plumbing, or anything like that cheaper. I've moved between developed and developing countries, and I have found that first world goods and services are more expensive in developing countries, the only thing that is cheaper is labour. In other words if you want people to cook and clean for you, serve you food, mend your clothes and fix your car, it will be cheaper. The cost of living only feels cheaper in developing countries if you consider the population of that country to be your peers and you generally do the same things for food, entertainment and running a household as them.
Yes, it seems rather disingenuous to lump different countries (or even states/cities within the US) into one ladder. 50K in San Francisco is a lot less than 50K in .. well, pretty much everywhere else.
http://cdn2.tnwcdn.com/wp-content/blogs.dir/1/files/2014/01/...