I agree. We do need people like that in our lives, and if we are open to learning the truth about anything, we will welcome their perspectives.
I will add that fallacious bombs dropped by mental anarchists also have value, too. I have come to enjoy trying to unravel why some stupid thing someone says triggers me. Usually, my triggered feelings point to a new idea or twisted concept I had never fully resolved.
I welcome the challenges now, which is quite freeing, and could care less about winning the argument. I get to learn something new and hone my views in the process, which is a reward in and of itself.