Putting dogs on a chain and leaving them outside until they die is animal abuse. Leaving dogs on a chain for some time in case needed is not animal abuse. Leaving a baby home is abuse, because they are not able to take care of themselves. Leaving children (say, 10+) home is not child abuse because they are able to take care of themselves.
Shamefully abusing animals is considered normal by a lot of people, abusing babies is not considered normal by 99,9% of people, and putting babies on a leash is considered abnormal by so much people that the percentage could just as well be 100. That is the reason why dogs are leashed and children are not.
Now I'd like to use a swear word because it took me half an hour to write this post.
