Why are Christians / theists always downvoted in this subreddit? (rant)

It astounds me that anyone who starts a comment with "I'm a Christian" or something similar, always receives multiple downvotes. Often, the theist is in agreement with the atheist, or if not in total agreement they're at least trying to find some common ground just to be told to Fuck Off! Look, I've been an atheist since 1985, come from a very fundamentalist Christian family, and very much dislike religion. That being said, I think it's important to be civil to theists who are willing to have a dialogue with users of this sub. These are the people who who are most likely to be accepting of the non-religious. Is that not want we want - to accepted be by society? This is my first post - I haven't been on reddit very long and rarely comment, but I've spent a couple of months reading post almost daily. It appears to me that this sub does not tolerate free thought, nor a difference of opinion. I would like atheists to be a welcoming people, not a bunch of assholes who are creating their own dogma.

Edit: typos and grammar

2nd Edit: I'm not talking about theist who are trolling. I'm talking about people who are genuinely trying to participate in dialogue.

3rd Edit: It appears that everyone wants a link - I apologize that I'm not quite prepared for multiple links. Here is one that I was reading today, granted it only has a couple of downvotes, but this person is clearly just sharing their opinion and not attacking.

https://www.reddit.com/r/atheism/comments/67lwa9/god_is_the_biggest_snowflake_ever/dgrhvr0/

I do realize that there are many reasons to get downvoted, but if you're trying to tell me that people aren't being downvoted just for being a theist, then I say you're being untruthful.

Final Edit: I concede - this is apparently all in my head. I've got to get back to work, thanks for your time.