In my whole family, we NEVER forget the cats and dogs (my parents have a dog, my sister has 2 dogs and 2 cats, my niece has a cat and I have 2 cats). I have a colleague that saves the cards until the cats come in from the garden, because then they have paws that can sign . She puts the cards on the floor, so the cats have to run over it!
I sometimes have my doubts whether people are going crazy all over the world, but the results of this poll made my day: I feel safe in community where 2/3rd of the pets sign greeting cards. And this is serious!