Ok...since I am officially the India rep here...I'll give my inputs.
1. These kind of incidents are as appalling to Indians as to anyone else. Such practices are banned and against the law.
2. This has nothing to do with Hinduism or any other religion. Certain social practices have developed in certain regions due to their past history that are sometimes still in vogue. Some regions (Rajashtan, UP, Punjab etc) have been the centre of wars and feudal battles for centuries and their medieval methods of 'justice' are still practiced.
3. India is as large as Europe and what happens in one corner need not impact or even known in any other region. Just as some barbaric practices in some southern parts of Europe do not directly concern the UK. Even in the US recently...some people practiced ritual human sacrifice. Does not mean every one endorses it. In UK some people still practice female circumcision.....does not mean everyone knows about it or endorses it. If it comes to light....action is taken.
4. Some remote regions (especially in the north) continue to practice certain systems that have been banned after independence in 1947. These are normally taken up by the police and courts if they are brought to their notice.
5. Villages in India (there are millions of them literally) are traditionally governed by the Panchayat (five elders) who normally would take decisions on the village rules and norms. After independence, this system has been kept in tact and integrated with the larger legal system of the states and the country as a whole. Major changes were not made. In other words...the panchayat still has a voice in the activities of the village though in many parts it is largely defunct and exists in name only. In some regions the panchayat is still powerful. There are no law books or lawyers here. Its all left to the 'wisdom' of the elders.
6. Many of these 'elders' are just that.... elders...nothing more. They are normally old, uneducated and often rooted in very rigid ideas of marriage, sex, women's role and so on. Most younger people leave the villages to move to cities...and that further dilutes the village modernization....and the words of some toothless old fogies still hold sway.
7. Some villages are so remote (no roads, no electricity, no railway)...that what happens in these parts is not even known to the other parts of the country. It takes weeks for investigating agencies to get there and find out what exactly happened....if they come to hear of it.
8. There are vast differences in different parts of the country with regard to education, development, family planning, women's role, marriage and so on. It is wrong to say that India is developed and still all this is happening. Certain parts of India are developed while certain parts are not. Some parts are still living in the 18th century and most of these people have never been outside their village.
9. Some decades back nearly 90% of India was uneducated and rural. Today it is only around 40% (500 million....more than the US population).....which is a vast improvement. This 40% will also get integrated with the rest of the country in course of time.
10. Lots of weird practices are prevalent in some regions of India even today. We are happy whenever we come to know of them so that it can be changed. Lot of noise is usually made in the Indian media about such matters. That is a plus. Westerners wouldn't even know about such matters unless Indian media make a noise.