A friend introduced me to one of her school's directors in the hopes that she'd get permission for me to do a guest lecture for her history students, and that guy treated me like I was a cockroach. She says he's a worthless POS anyhow, and I believe her, but I can't help but feeling like maybe if I was a little more presentable, he'd have been a little less rude. He wouldn't even look right at me. I wish I had said something, but then, she works there and it is her job on the line - not mine. I was so embarrassed for her. >:(
There's always going to be discomfort about being a little more presentable. You could be Stephen Hawking in a tuxedo and there would be more respect you could get if you dressed a little better. I'm very low class and I kinda look it but I've learned the hard way that most people who are judgy like that just can't be pleased. There's always something not good enough for some people.
It's easy to say though. That is a horrible feeling when a person treats you like you're subhuman. I hope you and your friend can brush this off without your professional lives being affected by it.
I worked with a guy who could be abrupt and rude to just about anyone. He wasn't like that all the time, but when he was it was best to stay out of his way. Hard to say what his exact problem was, other than the fact he lacked proper social skills and etiquette.