Another point - it also eliminates any annoying T-shirts-with-slogans, which disarms a lot of leftist stupidity.
And that policy can bite us back as well.
http://www.freerepublic.com/focus/f-news/1305601/posts
http://www.freerepublic.com/focus/f-religion/1822803/posts
http://www.freerepublic.com/focus/f-news/1701018/posts
http://www.freerepublic.com/focus/f-news/1653130/posts