I have several quilts from my youth/childhood that my grandmother had to patch. Not dog damage, more like I was making a "survival tent" with it outside and poked a stick through it, or I was using it as a cape and when I "flew" off of the top bunk it caught and tore on something.
Gran never really tried to disguise the patches, she'd put something handy there - sometimes even things like my uncle's old boyscout patches, or some MAC truck patch my grandpa had laying around.
I love all of the patches, they're all different and unique and to me they enhance the quilt and give it more history. And I kind of like that the old damage isn't really hidden, I can look at the quilt and remember the time when I was a "superhero", or was "lost" on a "deserted island".