As an atheist apostate who was raised in a fundamentalist, Baptist, Christian church in the Great Lakes region, it hits pretty close to home.
I was last in church a couple weeks ago for a funeral; it was a little weird hearing about the ways people from various highly-similar churches talked about Grandma's spiritual history as she was enlightened from her Christian Reformed early childhood to know a living and true God. Did she know the theological differences at age 10? We talked about the effect she had as the matriarch of our extended family bringing everyone together for decades by sponsoring an annual summer trip to a nearby Bible conference ground, and about how she justifiably ended that when the Bible conference lost their way and endorsed some speakers with relatively minor theological differences.
It's not "conflict" in the sense of the Spanish Inquisition - no one, as far as I know, would genuinely push someone off a bridge for being in a different sect - but around here they'd pray for the person to accept the truth, call for church discipline/excommunication/speaking bans if in a position of power, or they'd leave the church and find a slightly different sect that didn't make the wrong call on whatever issue was brought up by the council of 1912.
There's a paradox of intolerance at play: A group that aims to be universally tolerant cannot actually tolerate intolerance, and fundamentalist Christianity advocates a singular, accurately understood, unique truth at its core. You can and tolerate love those who hold different theologies all you want, but if you believe in one absolute universal truth as a lot of Christian culture does, then anyone who believes even a little bit differently is not right, which is to say, by definition, they're wrong.