what a way to run a business

I went in to change the nosepads on my glasses. When I got home, one of the lens had huge scratch carved in it, but they did not mention it when I picked them up. I went back to the place the day after and the owner says he'll get new lens for $99, fully compressed and with anti-glare coating. I waited for three weeks and he calls and says he can't do it for $99, and raises the price by another $100, when he's the one that should pay me for the damage! I demanded a full refund, and got $100 credit, but I'm never going back to that place, where they can't even do a simplest job properly and responsibly. What a way to operate a business!
I'm starting to think that they made the scratch on purpose...