They exist because the long arm of the law doesn't reach remote places. In extremely remote and isolated villages in central India, these "khaps" are the only justice system in existence. It's something like the sharia courts in some parts of Pakistan, which operate outside the regular legal system.
This is why India needs to urbanize, on a high priority. That is as important as "make in India", "swatch Bharat" and so on. Urbanization would solve many social ills - the presence of these primeval tribal courts, caste and religious prejudices, etc. It is easy to have caste/religious differences when people live in small isolated communities, cut off from the rest of the world. It is not so easy to harbor such prejudices if people live together in a city, sharing apartments and civic amenities like schools and shopping centers.
On this topic too, unless India urbanizes, we cannot afford to extend our legal system to everybody. We are not so rich, that each village can have a governmental law court, and trained lawyers and judges. People have to form cities, rather than live in scattered villages, to make it easy for civic amenities to be provided - electricity, water, roads, hospitals, law courts, police stations....
The rural-urban ratio is way too high, for India to have an efficient social system. Compare it with advanced countries, to get an idea.
LOL I wish so too, but it won't solve the larger problems. But I won't complain if the men who ordered this rape are themselves brutally sodomized.