I just have my dog's name and a telephone number. I find having an address isn't really necessary since if they get loose in my neighborhood, they probably already know where they live anyway since EVERYONE knows my two. And secondly its just.. not necessary, IMO. What if I move? What if I go out of town and bring them with me and they get loose there? An address won't do any good then.

Oh and I don't see how having their name on it or not would make it "hard" to prove who the real owner is. If you have your dog microchipped, that's all the "proof" you need.