Ignorance. They know nothing about it and that allows people to fill the gaps in their knowledge with whatever bias they have. It's also true that all people hear about are Islamic terrorists. Obviously the jihadists represent a very small number of Muslims.
I don't consider terrorists as a part of any religion. Religion teaches to love and not to kill.
Which religion is that? Christianity certainly don't, and Islam seems to mirror it. Judaism has always been pretty open about being exclusionary in WHO they love.
Now, they do all talk out both sides of their mouth... "Love everyone as your neighbor, but stone gays and rebellious teenagers" etc, etc, ad nauseam
Really?
I think you mean something a little bit different that what you imply. Because what you imply is that the Jews, The Christians and the Muslims stone gays and rebellious teenagers about the same.
And it's the most curious thing, but here around where I live there certainly haven't been any stonings. Ever. Even back when it was populated by Indians. There may have been a few tresspassing fools of warring tribes or white men who were staked out in the desert sun on top of ant hills.
But hey, there weren't fire ants in North America back then.
I'm implying, no, straight saying that what religions publicly teach and what they really believe are always at odds. Currently, Muslims appear to be the most violent religious group out there. I think anyone disputing that is not paying attention, regardless of what the more peaceable majority think. And yes, they are the majority, or the world WOULD be overrun. Or at the very least there would be global war. But the past history of the other two major religions I cited isn't any better, except that Muslims have rapid firing rifles and even bigger "toys" that were simply unavailable to the Jews and Christians before the world made them chill the fuck out.
Here in North America, it was less than 3 centuries ago that they were trying "witches" on the flimsiest of evidence and hanging them. Christian hypocrisy runs deep, and has for two millenia. The Romans once condemned Christians (and Rome was a tolerant society by nearly all accounts) as "stealers of children and poisoners of wells" of those who worshipped other gods. Why exactly Constantine converted and took the Christian Cross over that of the gods he previously worshipped is unknown, but from there until near the end of the Renaissance, Christianity spread very rapidly... by the sword.
I do not find it in any way surprising that Islam's adherents act the same way. Religion "forgives" terrible actions if one does them in the name of "god". It can convince otherwise good men that it's perfectly ok to murder, rape, and pillage so long as those heathen bastards refuse to convert. This still goes on in Africa as well, where the Christians and Muslims and Animists in and around the Congo have been killing, maiming, raping, and sometimes (usually in the case of Animists) eating members of the other group.
I grew up Christian, and it was very hard to overcome it. So, yes, there's a special black place in my heart for Christianity. But that doesn't mean I don't see what goes on with the other religions. Most, if not all, theistic religions rely on violent, horrific imagery to promote the "good" of their god. Whether they make that imagery real or not seems to very much depend on the age of the religion. This is stated as my own opinion, I have no hard data to back this. But anecdotally, and historically, the theory holds water.