Often questions are asked why Indian love snakes and pay respect to them like deities. There are many answers to this question. Often people worship any object or concept due to two reasons.
Number one, the people have benefited from the object/concept and they further do not want to stop the flowing jet of benefits.
Number two because ancestors have worshiped them, so the present generations should worship them.
In first place the number one reason is more analytical and scientific, while number two is equally superstitious if followed blindly. The snake reverence in India, as claimed against by many foreign cultures, is a more a scientific and environment friendly observance.
If we closely peek into the Indian subcontinent then it has been more of a fertile land, where proportions of elemental mix in the soil is perfect. The Basins of Ganges, Yamuna, Saraswati, Godawari, Chenab, Krishna, Brahmaputra, Kshipra, etc have made it a land to be appropriate for agriculture and vegetation growth. Second to Africa is India where such diversity of flora and fauna exists.
So coming to the point Indian settlers were more attuned to the agriculture based economy and snake played an important role in this. How ? lets see. The worst and perennial enemy of any food plant and food are rodents and they still are responsible for the 20% of food grain loss every year in the world. The snakes eats up the rodents and maintain the ecological balance of rodents population. A 1% decrease in the snakes population can result to the rise of 5% increase of the rodents population roughly. (Its not an accurate figure but an assessment over the feeding habit of an adult snake and sexual maturity age of rat.) So you see what more harm can the 5% more rodents can do to the agricultural reaps.
Snakes are very beneficial to farmers and this was known to Indian way back when they have started to organize the agriculture to produce the food grain, probably much before the Europeans and other dwellers. Killing of snake was very heinous crime unless the snake itself was a mess. In that case the another ecological food chain agent Peacock was often allowed to roam in the agricultural land premises so that they can check over the expanding population of snakes.
In a nutshell there was perfect ecological balance in such way that no external agent like chemical pesticides, rodenticides, and germicides was used.
Now one must wonder how such information was passed on to generation to generations. Well if someone is able to see the Shiva-Parwati family, then one can understand the perfect ecological balance is depicted in the entire family association.
Snake is dear to God (Lord) Shiv while Rodent or rat is vehicle of Ganesha (son of Shiv). Another son of shiv Kartikeya has its vehicle as Peacock. Now looking at the Shiv's Vehicle it is an OX representing all the cattle sort herbivores like stages, deers, etc. and Tiger,Lion is vehicle of Goddess (Lady) Parwati.
Rodent is checked by Snakes,
Snakes is checked by Peacock
Peacock and other Herbivores are checked by Lion/ Tiger.
and these animals having animal instincts and tendencies are checked upon by the Lord Shiv and Lady Parwati the epitomes of creation and destruction.
This is known as perfect ecological balance to keep life running. It is a fact that base of every country is agriculture and herbivores while some countries have entirely this as their base, while others have few other options also to include other things in their base because agriculture is feebly absent in large quantity their.
That is why snakes were revered because they were important part of food chain. To maintain the environment the perfect maintenance of food chain was necessary and Indian knew this. So they always took care of snakes and to spread this message and implement it, the system of religious affiliation was adopted and not to say under religion it became safe.
But due to this blind faith, superstitions rose and gave the foreign illiterates ( Like Lord Macaulay) to say that India is land of snake charmers. I am saying illiterates because if they were literates then they would have gone for a question that " Why people of India loves snakes too much?". Now they are realizing the facts that India has been environmental friendly country since ages.
In this regards many stories were written and told by old people to convey the message that how come the snakes save human kind from disaster. It is something like if you can see a slight change in environment but cannot express it but still you have to say because of the matter to avoid the future ecological disaster, then only way is to devise a story and tell it to kids so that they could remember and understand when they get the knowledge of that level. Even if they not happened to have the knowledge of the erudition level then also those kids will be saving the environment. Whatever name of the scripture we know like puran, naag lok, nag vansh, etc. are such constructive stories to tell about the snakes importance in agriculture and ecological food chain. Snakes always remained mysterious because of their nature of hiding and remaining aloof. And unlike other animals they always have been attractive because they never had any limbs yet they were ferocious and surviving on this earth. And probably this makes snake more elusive till date to many around the world.