I'm ashamed to say, when I went to high school, it was common practice for kids in the stands to chant "the ref beats his wife" - and no one really thought twice about it.
The worst I've heard these days, fortunately, is "we wanna ref....we wanna ref".
On a similar note, the other day, as we're walking off at halftime, some bozo in the stands yells out "terrible half ref, terrible". I looked at him, and said "save your applause - I have a really weak finish!"