Ellen Degenere's commencement speech

I love Ellen shows, I like her personality and her sense of humor. But, I totally don't understand why Tulane University invited her for commencement speech. She began to sound almost serious at multiple points during the speech, but she didn't get serious at all. She might have delivered hidden profound messages but honestly, I didn't get any. Please enlighten me if you do. It could also be that the university administrators just want to end the ceremony with something light and fun. Anyway, the speech is funny.