The only time I've seen them were in high school. Our class had to do a pursuasive speech, with half the class doing abortion. The class itself was already pretty rowdy, but every since abortion speech turned into religious arguments (I use the term 'argument' lightly). Figuring I'd get otrn apart anyway, I chose Atheism as my topic. Now at the time, I was a devout Catholic, so I did my research, quoted a few notable atheists at the time, and creatively filled in the blanks myself.
Now my friend really was an atheist and quite an outspoken one, but no one took his anti-religious spouts seriously. I made one speech in favor of atheism (which I did just for the grade), and I suddenly learned about Mr. Chick really fast!