There is also such a thing is delayed neutering that no one has brought up with regard to dogs. We have a rottie-mix and when I took him to my vet she told me to wait until he was 1 year old to neuter him. I ended up doing a lot of research and I am now waiting even longer. I have always been a spay/neuter proponent, but if you look at the research now being found, medium and large breed dogs are at risk for a lot of health problems of being fixed too early (before 2 years). Apparently because they don't go through the entire cycle of growth hormones they end up having greater risks of bone cancer and other issues.
Here is an article that sums it up well: http://www.dogsnaturallymagazine.com/spay-neuter-and-joint-disease/
There are better more scientific analysis' to be found if you look harder. I was initially worried about having an intact male dog because we have always spayed/neutered our dogs early on. He has no dominance issues with my kids and is really docile and sweet. He has no wandering issues but he isn't left in our yard alone.
Everyone has to make the best decisions for their pets. We wouldn't have the diversity of dogs we have now if they hadn't been bred for specific jobs. We shouldn't blame or hold accountable the responsible owners and breeders for the terrible dog owners and puppy mills out there.