Atheists! do you find it difficult to take people of 'faith' seriously?

for me, knowing that someone is a believer taints just about everything they do or say about anything. after all, i figure if they can believe all the nonsense they believe in, their world view is simply not based in reality and therefore, i treat them almost like simple-minded children. how do you cope with the 'religious' mentalities you encounter in everyday life?