[OkayPhysicist]

You've described all social phenomena. Just because something is socially constructed (i.e., exists only through other's belief in it, e.g., Tinkerbell logic), doesn't mean that the widespread belief in that thing isn't powerful in that it can effect concrete conditions.

Money is socially constructed, in that if everyone decided money was worthless tomorrow then it would be. But today, I still need money to eat, or have housing. The Law and The State are socially constructed, in that if they were not generally accepted by the masses they could not perpetuate, yet if I break the law today I quite likely will be violently thrown in prison.

There is a difference between acknowledging that something exists and granting it power over you. I would be doing myself a disservice if I actively ignored the existence of religion, for example, because even if I reject the notion that God exists, plenty of other people I interact with will not. And their belief in that fixed idea will affect their perception of the world, myself, and my actions.