For perspective:
The average number of deaths per year from:
Dog bites: 16
Forklift Truck Accidents: 68
Lightening Strikes: 82
Car Accidents: 43730
The average number of deaths in children per year from:
Dogs: 10
Balloons: 11
Playground Accidents: 15
Buckets: 22
Human Caregivers: 826
American data where Pitbulls are legal in several states. Taken from CDC online.
Now you can argue that dogs are not necessary, unlike car travel, although as non driver, I tend to disagree with that sentiment, however are balloons necessary? Playgrounds? No, they're not but they bring pleasure to many and given the rarity of fatality or injury are relatively safe.
Dogs bring pleasure to my life and to my children's, they provide us with exercise, social enhancement, stress relief, warmth, love and help us to feel safe. Training with them is a great source of amusement on rainy half term days. My children and yours would be safer in my house, with my dogs, than in your car, at your party with balloons, at the playground or being looked after by Granny, statistically speaking.