Should I call Chapel Hill and see if they will add an extracurricular to my application?

I did not know hobbies could be considered extracurriculars. My grades and standardized test scores are above average for Chapel Hill but I have very few extracurriculars. I have been studying rhetoric and writing short stories, poems, and novels for many years now in my free time and I have a portfolio of my writing on my computer if they were to desire samples.

Would it be wise to call Chapel Hill and ask about this? Would it help me considering it’s a long time extracurricular, or would it hurt me?