That's not entirely true. I had a button on my 3ds stop working from being in my pocket all the time. It was my fault, but Nintendo classified that as normal use. I thought this made sense as it is marketed as a portable device.Next time get a warranty and be more cautious with your stuff. You can't really fault anyone but yourself for it breaking. As I recall, any damage done to anything after it's in your hands is at your expense. Everyone should know this by now.
I'm glad they decided to cover this for you, though. I have always boasted in nintendo Canada for their over the top customer service. They've always treated me like I was Mr. miyamoto himself.