I will answer from the Biblical standpoint.
Faith is never blind. Biblical faith is qualified by Who that trust is in: Jesus. Faith always has its eyes wide open and focused on Christ. After all, if faith was blind, then I could have "faith" in anything that I wanted and it would be valid.
Faith means trust in or reliance on Christ, who is himself trustworthy. How do we know this? By what He has already done for us. How do we know what He has already done for us? By people who used their senses and recorded legitimate, historical eyewitness testimony in the Bible.
Why is religion important to human life? John Calvin once wrote that the human heart is an idol factory, meaning we, as human beings, are engineered to worship something. That something is our ultimate concern whether it be God, money, politics or science. And that's all religion is: our ultimate concern, which satisfies the desire of our hearts. One need not have god to be religious.
I will speculate and say that life with religion means life without an ultimate concern. Even folks who don't believe in God have an ultimate concern (e.g., science, evolutionary biology, etc.). This tends to suggest life without religion is life without humanity.