No we don't live in a perfect world, and we have to apply our God given logic and experience to the judgments we make. I don't care for mandatory seat belt laws, but I wear my seat belt. Your reliance on absurd extreme examples is like the person who says, "what if my car goes into a lake or off a bridge and I can't get my seatbelt undone?" If that's your real worry, then fine, don't wear it, and I'd much prefer the law wouldn't punish you for doing so. It's moronic because statistically, living in the "Realville" of conservatism, where experience, logic and knowledge hold sway, it's always smarter to wear a seatbelt, regardless of how many absurd hypotheticals you can come up with. Similarly the odds of a dog being saved from a house fire or flood by virtue of being chained outside are much much smaller than the dog being provoked, harassed, attacked or hanging himself.
Look, if your dogs are so ill-disciplined that you can't trust them in your house when you're away, go for it. Chain them up outside and leave them there. Just don't expect me to believe you're a responsible dog owner, or that you're doing what is in your dog's best interests.
My dogs are in my home with me, I have a kennel outside and a place to tie up a dog if need be. I use each option depending on what is going on. I don’t as a rule tie up a dog- but have been known to temporarily do so. Difference is I don’t think it is my business how others care for their dog unless I know it is being abused. As to far fetched ideas of dogs burning up in houses I have actually known it to happen twice. One of our friends had a little dog in the house and a big dog tied up outside when their house burned to the ground. They tried to get the little dog out of the house but it hid under the bed and burned up. Another time the dog burned up in the house while the owner was at work. It is not far fetched to say a dog may not be perfectly safe inside the home.