Speaking solely for myself, I've found that my spiritual / religious side helps me to set goals and to communicate with my intuitions. Rationality is simply a tool for implementing those goals, and processing/evaluating that intuitive data.

I've honestly found the hostility towards "spirituality writ large" here rather confusing, as the majority of the arguments seem to focus on a fairly narrow subset of religious beliefs, primarily Christian. I tend to write it off as a rather understandable bias caused by generalizing from "mainstream Christianity", though, so it doesn't really bother me. When people present actual arguments, I do try and listen in case I've missed something.

Or, put another way: Rationality is for falsifiable aspects of my life, and spirituality is for the non-falsifiable aspects of my life. I can't have "incorrect" goals or emotions, but I can certainly fail to handle them effectively.