White Dress
"I don’t want to wear a white dress. While, as stated in a previous answer, it didn’t originate as a symbol of purity, it has long been associated with that, and I find the focus on a woman’s so-called purity to be weird and disturbing. Wearing a dress in a different color is a way of saying that my sexual history is nobody’s business but my own and the point is that I’m making a life commitment to someone I love, not whether or not I had sex with anyone else before."
Why? Because they don't want to follow every standard traditional thing?
If someone tells me that they don't understand some tradition a take them as an illiterate person. You don't need to follow, but understand? Just research it.
You can choose what you want.