I agree that there are pet-people and non-pet-people. And,the differences go far beyond whether or not an individual likes or dislikes pets. I suspect that when challenged these mixed couples will discover huge value differences that are just not reconcileable. I suspect that:
No pet person can be both sane and a neat freak or germ-o-phobe. But, a non-pet person could make a reasonable attempt at neat and germ free existence.
Pet and non-pet people will differ in how they treat those with less power. Kindness or cruelty.
Pet and non-pet people will differ in whether they place the value of things ahead of the value they place on relationships.
As a pet person, I do not understand neat freaks or germ-o-phobes. Due to our value differences I believe that germ-o-phobes are somewhat delusional and that neat freaks could surely find better uses for their time. (I can not imagine being satisfied if my tombstone read "He kept a neat house".) I know that I have caught far more illnesses from co-workers, associates, and the people I have contact with in daily life. Somehow, I have even found ticks on me when I have walked on the golf course with out my dog!!!
As a parent of a two year-old, I do know that my son has scattered gallons of bodily fluids all over the house and directly onto both me, my wife and even onto our dog. I also know that after a year of daycare, my son has passed far more colds and viruses to us than we have caught from our pets. Despite this I agree with that writer who said there is no comparing the value I place on my son and the value I place on my dog. But, I hope that I will be able to teach my son to appreciate animals so that he can enjoy them the way that we do.