I really expected this as well. In my mind, there is never any justification. My time is worth the world to me, and so if you would like me to dedicate it to your task, that is going to cost you.
You never, EVER work for free. Not even for a charity. You invoice them. And you donate that invoice. And you get a receipt for your taxes. In this way, they can fully understand and appreciate the true value and real cost of the work you have provided for them. Everyone's book's are square. No one is left out in the cold.
When you work for free, you devalue the work that we all do. Many thousands of web devs still bitch about client's who won't pay or scoff at quotes, because "I've got a cousin who can do that." Then go get your fucking cousin, because my time has a tag attached.
Your time is worth something, and it shines in your quality. Believe in yourself.
