I don't even need to get into the question of whether boo-ing salsa songs is racist (it is), to say that it is not nice. It is not a way to communicate concern for anyone but one's self. Even if it had no minority racial component at all - if people boo-ed a country song, say - it is mean to tell people at the same party, who also payed money, who are your fellow students, to boo the things they like because they're not what you like.
David Anderson, a pastor of a large multiethnic congregation in Maryland, wrote a short book recently with the catchy title Gracism: The Art of Inclusion. The book has a single point, taken from I Corithians 12, that there are members of the Body of Christ who are more vulnerable than others. It is the duty, calling, and self-referential privilege of those who are not vulnerable to care for those who are.
I do not know how many people wanted to hear a salsa song at the President's Ball, but I suspect it was a minority. I suspect many of those who were happy to hear a salsa song were in fact actual minorities. I also suspect that they did not feel cared for when their classmates booed. I doubt they felt appreciated, that people were glad to have salsa lovers at the ball. Setting aside any questions of racism, I would be interested to hear someone argue, from a Christian point of view, that it's OK to boo when you hear a song you don't want to dance to.
Tired of talking about racism? Think it's time to move on? I think it's time to move on also. But I won't move on when so many people would clearly get left behind.