I don't know why I'm a photographer

[Garp]

Divine pretty much summarised it perfectly there from your text. I'll have a stab too, though I'll be putting lots of words in your mouth, based on what I've heard you talk about in the past, if you're not so keen on what he came up with.

Why am I a photographer?
I feel driven by it, by a deep passion that's hard to put into words. A passion to break down the walls of the seemingly dull and dreary and reveal the beauty that is hidden in plain sight. A passion to make people stop in their busy lives, rushing from place to place, minds focused on everything but their surroundings and show them what they're missing. A passion to tell a story in a city of millions, without saying a word. A passion to stir memories, to invoke those magic words "Do you remember when ... "
Most of all, to me, it's an expression of love. I love this city, and I love these people, and these photographs are my way of saying "I love you"

Cheesy? Maybe..