Actually, I'm not quick to assume that they were making fun of the Mexican culture. They were having a "Mexican" night. Everything as Mexican, I suppose. I bet tey had Mexican food and Mexican booze also. Also celebrating Mexican. Sure they had some laughs.

But since they were almost all white Caucasian girls, and this was a sorority , thus an exclusive, gathering they get the axe.

If the mix were some African American , Asian and some brown skin girls then it would have been alright.

If that were the case then even the two signs would have been given a bye.

Hey, this is my opinion. I could be wrong

Dave