Some are. The ones that repress an entire culture seem to be that way. However, there are many sincere forms of religion.
The Hindus
Religion seeks to instill commonly accepted behavior. Individuals use religion as a framework within which actions will likely be accepted.
It is easier to teach and instill abstract concepts when you can represent them to the senses in various ways.
Parents try to instill values in their children.
Chief Joseph's father, Joseph the Elder was an early adopter of the Christian religion and instill these values in his son. Chief Joseph was a man of peace and lead his tribe from their home in Oregon to near Canada.
Believing oneself is no doubt the best way to instill confidence within self. And dear, religion is the path to achieve the Supreme Power and can be practicized at heart to attain peace of mind.
She tried to instill confidence in her students by praising their efforts.
Maybe with a voodoo doll (just kidding). No, you can only "instill" habits not emotions. For example, you could instill someone with good values or good work habits. But not instill them to love, hate, be happy or sad.
Teach.
Engrain, impregnate, impress, inculcate, infuse, ingrain, tincture, and transfuse are some of the synonyms for instill.
instilled
The point of a religion is to review human experience of a regional accord so to instill integrity and provide inspirational virtue for the new generations. Hence, if one can forgive poise and pride, the social plight of humans enmeshing in purposeful civilization is the historic gell that oozes like electroplasm from the rhetoric. All religion is thus.