I'm very traditional when it comes to myself not wearing white when I'm a guest at a wedding - right down to my socks.
An anecdote:
A family member wears a white dress when she goes to weddings. EVERY wedding. My mother's in the 80s, my cousin in the 2000s. I want to elope because of this, so she won't get a chance to wear white. Maybe I'm overly picky; quite possible. Here's the anecdote: at my cousin's wedding, the B&G couldn't find the marriage certificate, and the officiant said they had to go to another wedding, and please hurry up and sign it. Finally discovered my family member was fanning herself with it!!