Because religious beliefs and religious thinking is a natural by-product of human cognition and emotion.
Why do we find religions in every known human society (in history)?
My favorite answer is the one Michael Shermer (founder of The Skeptics Society) gives in his book "How we believe":
*"Religion is a social institution that evolved as an integral mechanism of human culture to create and promote myths, to encourage altruism and reciprocal altruism, and to reveal the level of commitment to cooperate and reciprocate among members of a community. That is to say, religion evolved as the social structure that enforced the rules of human interactions before there were such institutions as the state or such concepts as laws and rights. (...)
The principal social institution available to facilitate cooperation and goodwill was probably religion. An organized establishment with rules and morals, with a hierarchical structure so necessary for social primates, and with a higher power to enforce the rules and punish their transgressors, religion evolved as the penultimate effort of these pattern-seeking, story-telling, myth-making animals."*
(Michael Shermer "How we believe". page 162)
Nice post, thoughtful comments - thanks.
Historically thinking, I think it's helpful to accurately record what we know people did. Taking a leap to explain why people do what people do is maybe a bridge to far. Myths/parables were created - that's a fact. Religion was crafted and leaders emerged, that's a fact. I don't know if I'm missing a link but I don't know if religion was created in order to promulgate myths.
I don't know that I am so much more evolved than people 2,500 years ago. I'm more informed. Because I'm more informed I'm an atheist. That's how I see things, rationally. I don't know what I would believe if I only had access to the collective and disseminated knowledge of yesteryear.
I follow the theory that belief is more of a compulsion than a rational conclusion. I feel compelled to appreciate the natural view of the universe and compelled to dismiss supernatural explanations. I suspect I would have the same compulsions no matter what my access to information was. Johnathan Haidt (The Righteous Mind: Why Good People are Divided by Religion and Politics) argues that we don't have a truth seeking mind; we have a confirmation seeking brain. Thus, most of us, me too, I expect, can't be reasoned from a position I came to emotionally. If that's true of human nature; it's possible that it's been true for thousands of years.
Shermer exhibits an attitude that I find rational and perceptive. IMO it is a mark of courage and honesty to look at the world as it is—to accept and try to understand nature without making negative judgments.
The religious impulse is present in humanity for reasons, and it behooves us to recognize and understand those reasons with dispassion. Perhaps we might also recognize the religious impulse within ourselves and cultivate the best and highest attributes of that impulse.
Equally important—the modern tendency by many to angrily denounce all forms of religious practice—that anger must be recognized and understood as a necessary natural phenomenon, following from the human condition.
Some of those angry denouncers are the ones who say there’s no such thing as free will. If they are correct then they are angry at something that had to happen under natural laws, and that anger seems irrational.
Of course they have no choice in the matter I suppose.
Religion was invented by scared people to keep others in line. "If you do this, god will punish you!" "If you are a nice person, you will get into heaven!"
Think about how much better you felt as a kid when you lost a tooth... Then found out there might be money in it for you!
Religions take hold because people want to believe they know something 'special', that puts them above others of the 'common herd'.
Wander up to someone and say, "Hey! Let me tell you a secret! Not many people know this, but you have been SPECIALLY CHOSEN to receive this knowledge...!" and that person will probably be intrigued and flattered.
They will not only know 'the secret', but the fact that they have been chosen to hear it makes them feel 'significant'. And once they've locked onto how this special knowledge makes them, themselves, special, they'll invest their own pride, their own self-value, their own purpose in life into it - even if it's complete bollocks.
Particularly if they are poor at the concept of critical thinking, and seeking evidence for 'knowledge' - which is why religions almost universally detest any form of education that is not inherently religious.