Dog eat dog world?

Believe it or not, one of the four girls I am babysitting today just got bit by a dog. Serious. The only thing that stopped her from being hurt worse is she was wearing a costume. This dog bit the wrong kid (the daughter of an on duty Calgary Police Officer, who is now out looking for it). This dog, apparently, ran up out of no where and attacked her, then ran off. The neighbours who witnessed it and said the kids weren't even trying to get this dogs attention. It went after them. Now I have a little girl sitting beside me who can't go outside. I have to make sure the door is shut. And no honey, dogs can't jump very high.

Damn dog. Damn dog owners. Why are there people letting their (aggressive) dog run around biting small 5 year old children anyways?