I'm curious as to why this punk doused Buchanan in salad dressing. Because it's free at the campus cafeteria, because he thought it would stain more than water or soda or some other easy-to-fling liquid, why? It's one of those random details that sometimes stand out.
The dousing in salad dressing was symbolic. The dressing was Ceasar, symbolizing Cesar Chavez. There is a big to-do on Flynn's blog about some other trouble that occured that day at the college in a confrontation between the event coordinator and an liberal professor.