Dose religion really help mankind overall?

It seems to me that religions grow in membership during times of woe and hardship.
Would it not benefit the worlds religions then to foment divisiveness, and clashes between locals who have lived together for generations? "The Church" like any entity or institution needs to survive, and survival depends on growing the flock, and to do that, it helps to have people in misery so that they can receive comfort at the hands of GOD.
The missionary religions, by imposing their rules upon the converted regardless of their living circumstances, can and do incur further hardships upon them. This happens when the influence of the church is whored out to accomplish the desires of man. This happens when contraception is turned into a sin and birthrates skyrocket, or when the missionaries vocally spurn any group that rejects their teachings (loosely applied term), it may cause any who have converted to be at odds with their neighbors.
I know that churches do a lot to provide community and support for it in places where freedom of religion is accepted. Although they do have the spectre of sexual misconduct by priests in these comfortable parishes. But in places where times are hard and there is no law of religious freedom, religion causes increased division among members of those communities.
I am not Muslim and I know little of the practicing of it. I have though noticed that it seems like the extremist clerics use the deepset love their followers have towards the prophet Mohammed to fuel hate towards those who do not follow his teachings. Much like christianity used  those same tactics during the crusades and the Inquisition. In fact I see many parallels between religious growth tactics and those used for war.