I've basically started collecting various websites and sources of information on kilts and their appropriate wear, as well as a large collection of pics of both famous and not-so-famous people in all manner of kilted attire. After having a discussion about it with her I'm going to ask her to look through all of it with me.

In reality, some of the information points to her being correct. Not many people wear kilts, and most of them that do wear them for formal or celtic events. However the evidence is clear that casual kilt wearing, especially in North America is growing rapidly. Kilmen.com has a lot of really great stuff as well. Above all, the pictures tell the story. Pictures of a dozens of celebrities wearing kilts in both formal and casual fashion. That will say alot to her.

Eventually, I plan to wear it out and ask her to just come with me for a couple hours and see what people's reactions are. When she sees that they are positive (or that most people really could care less), hopefully she will feel better about it.