I think Science and medicine are yet evolving. They are not totally grown up. But nature which is still being researched to find answers possess many secrets. In olden days, our ancestors were very intelligent to wrap up many good things into some kind of package and called it rules and regulations of our shashtras or culture and instructed us to obey. The Temples of Palani (totally made of 64 herbs- which are curable of many chronic diseases) and the temple built by patanjali in Chidambaram, Puri etc were of some formulae. Recently, scientists unraveled the mistry of planets having some gravitational force called magnetic waves which pulled all the planets as per their power to hang and float.
These waves were discovered and demonstrated by some group of scientists recently. All the temples in India were built according to some Geo planetary positions and calculations which were beneficial to human race. As we are more and more influenced by the west, and for our own convenience, leave out/drop our customs and traditions and also some performing them without the reason and knowledge or benefits being understood, In today's world, there are very less number of people who know the reasons and or can prove the point, do not want to come out and prove.
Some day, the same western researchers would come out and say these are the reasons, that you should not do these things, we may accept but after their showing / demonstrating the proof.
So, in my opinion, there are only two alternatives for such queries/demands :
1. Accept and follow their dictum
2. Reject and move away from the customs.
Wait for the day, when the entire country awakens with knowledge and dumps down all the rituals and becomes nirvana like it happens in the west.
Hope, somebody someday will undertake the research and prove that God is there or God is non-existent.