I was wondering how many here fix their own flats?

Yesterday morning on my way home, I met a woman walking her bike along the MUP. She told me "I have a flat tire."
Being the gentleman that I am, I replied "We can fix that." She said " I am just going to take it to the bike shop." (Approximately 4 miles away) My mind went "Why?"

That got me to wondering, how many folks ride and don't or won't fix their flats themselves. Also, why not?