I beg to differ. In Aug of 07 I lost my patrol partner of 9 years. I've lost family, friends, my father, stepfather, father-in-law... I have 2 children, one of whom when born had some issues that luckily turned out OK, but at the time...
Anyway, the point is, I never shed a tear through any of that. Be strong for the family, and all. But when that stupid dog died, it was a solid 2 weeks of pure emotional hell. Felt like someone cut off one of my limbs. For 9 years that dog was my constant companion, never more than 20 feet from me, even at work and at home. You get VERY accustomed to their presence, and in many cases, can become very emotional dependent on them.
Let's also not forget that for many people, a dog is a surrogate child. They don't or can't have human children, and so the dog takes that role in their lives. Do you think the significance of the animal to them suddenly ceases upon its death? The value of a life, animal or human, is relative to the value that the individual mourning places in it. I know plenty of people that treat their dogs far better than some people in my neighborhood treat their kids.
Just because these people here don't tie their dog to a tree in the backyard and forget it exists, does not make them lunatics.
it is so hard to lose our friends and companions.
He was truly a gentle giant and always willing to be loved on by all. I think he touched many souls in his lifetime and probably showed many people, who would normally be afraid of a dog that size, what a great dog he was! 
