You'd feel guilty about turning a dog out on the street. There aren't so many good reasons to keep a dog muzzled in public. You can buy a dog's affection with a squeaky toy. A dog will be eager to walk, rather than getting a taxi. Most dogs are really good with children.
Dogs have a highly-developed sense of smell.
Men, on the other hand, can quite happily wear the same pair of pants for a fortnight. A dog is more useful for tracking down criminals. A dog might actually take a bath of its own accord. There's more chance of your dog being able to operate the video recorder. You can buy a choke-chain for a dog.