Can I ask a sincere question directed at non- believers?

Just wondering why posts by Christians on this site seem to incite such hate and demeaning comments. I get that you don't believe as we do and that's a personal choice. I guess what I don't understand is why it's not ok for us to believe just as strongly in our God as you believe that there is no God. You state your opinion on the site and in some cases state the reason for your non belief. Why is it offensive when a Christian does the same? Sincerely just want to hear your thoughts on this. Thanks!