My colleague and I were discussing his topic on science, which was about taxonomy. Another colleague overheard what we were discussing and he butted-in and asked "What's the importance of that to our salvation?" I wasn't able to answer because I got mad and I was worried that if I gave my answer it'll just create an endless debate on science vs. religion. And we all know it's difficult to reason with a religious.
My friend said that I shouldn't mind what my colleague asked, but it really bugs me when religious people ruin intelligent conversations by including their beliefs in everything they say!