Very large fraction of US population is paid $30 an hour compared to Indian population which makes scamming not worth the trouble
I live in India and I've worked in the US I know Indians just have too much time at their hand, so even schemes which take a lot of your time with little payoff are worth it here.
And the reason people don't use their time to achieve something more productive like starting companies etc...is because government procedures are very hard to understand, and you get penalties left and right, even starting a micro industry like machining shop is hard, power is not available continuously even at top industrial zones in India, fixed cost of electricity connection is high in industrial area and government is very insensitive to business owners so only very large and the ones close to policies are able to navigate.
The biggest problem isn't even market in India which has lot of demand, it's the costs you didn't plan for which seem low on surface the deeper you dig, the costs just keep increasing untill you are left with nothing and in debt so starting a business isn't very popular here and people limit the size of their success to not get in trouble.