gitana1, I have agreed with you throughout this thread. I don't know why you suddenly think I'm spouting contrary "nonsense".
I thought I was pretty clear in my post that "group-think" is no excuse for such obnoxious behavior.
But that doesn't mean I'm wrong as to its purpose (however unconscious). Trust me, the misogynist chants and songs (at frats) far outnumber even the racist ones.
Other such "group bonding" tasks including climbing the local water tower, vandalizing the administration building, painting grafitti on the frat next door, stealing a rival school's mascot-statue and so forth. In each case, by joining together to do something forbidden, the group reinforces the idea that those who did the deed "belong" and everyone else is an outsider. Keeping the secret afterwards only strengthens the bond in the name of "trust".
The only way to end such episodes is to integrate such groups.
P.S. Although chanting when one thinks no outside will hear is a long way from lynching, they are not unrelated in motivation. Good (that is, "bad") example!