Full disclosure: I am a former evangelical/pentacostal Christian, and did just that trying to fool myself into being straight. (I'm better now. )
I guess I see it differently. Are they tribalistic? Sure! But we ALL are! Every single one of us, whether we like it or not, separate the world into "us" and "them." None of us would put KKK members in our "us" group, for example. Does that make us bigots against racists?
Maybe.
That said, the Unitarian-universalists would be a church that does not separate the world into believers and non-believers. Further, the United Church of Christ, as well as being affirming are also very lax in their "heaven/hell" theology.
But these places are tribalistic because humans are tribalistic - they're doing nothing less than human nature. And for the most part, I think it's a subconscious measure.
But Evangelicalism and Fundamentalism is so appealing not because they don't have to think, but because it's a place to belong. It's not that they don't think, but it's that they try to advance along the tribalistic thought. Very few of us have thought through our personal philosophies from the ground up, myself included. To the extent I have, it's incredibly emotionally taxing and isolating.
But these people do think about ways to make the world a better place. It's just that their thoughts on how to make it a better place and ours are completely different. They see a world where individual churches join up as the center of society, responsible for caring for the poor and those who have come on hard times. Many larger churches have a Harvest Center or similar that distribute food to the community. One Catholic church I went to as a youth housed homeless men in the winter. The Salvation Army is both a church and a charity.
That's the more devious piece of neo-conservativism... It's not that they want no safety net -- it's that they want Christianity to be the safety net. To them, government cannot do the job effectively because it does not submit to Christian principles and further, hinders Christian charities by making them less needed.
If Christians don't center as the core charity, a fundamental piece of their evangelism is cut off.
In this, we agree.
My thinking above is heavily influenced by Eric Hoffer's "The True Believer." The book rocked my world shortly after deconverting. I don't agree with all of it, but what book can we? *laughs*