I think that the views of college kids will echo those of adults. As an adult, I'm sure some of your own friends have greeted your vacation plans with "You're going to Disney AGAIN".
People are ignorant, misinformed, or just don't know much about WDW. You'll find this among adults, and among college students.
The thing about college though, is that you have a much bigger population of people than you do at a high school. Not only that, but you have people from all different areas and backgrounds with all different interests. Your son might meet people who love Disney, and he might be met with some looks when he tells them that he loves going there.
But the real question is...WHO CARES? People like different things. Different strokes for different folks, ya know? I like Disney, and I do defend it when people roll their eyes at me, but I for the life of me think that watching football is boring and pointless, no matter how many times people try to explain it to me. Part of life is tolerating others preferences, as well as learning that not everyone will like yours.