I do not have reference handy, but recently read (on HN itself, I guess) that there is lot of interest among programmers living in "limited-opportunity" places in India to work on Bug Bounty programs. Obviously, one reason is time on hand. Other motivation could be the bounty itself. Even < $100 bounty is significant income. Thirdly, this honor badge is a ticket to a job interview, if not a job itself, in companies in bigger cities and possibly a better quality of life.

Again, I am theorizing without providing references.

you're right on all counts. add in the indian love of being intellectual or being associated with someone intellectual(you know the guy who discovered the video deleting bug? that guy works at my company!)

Payouts tend to be in the $250 - $5,000 range, IME skewing toward the bottom end for most bugs. If it takes 1-3 weeks to find one valid bug, economically that's not going to make sense for an employed US-based developer to spend their time pursuing. Those figures could allow for an income in the range of $10-$20k, which is ₹1M -- this chart gives an idea of how much money that is:

http://www.numbeo.com/cost-of-living/compare_cities.jsp?coun...

There are a lot of Indians (~1.3 billion), if even a smaller percent of them are programmers, thats a lot of programmers.