I can't take much more of this; it ruins whatever I am reading. It has become so common and I have no idea why? Do people not want to get it right? It is puppies, families, hobbies, butchers, bakers, potatoes if you are writing about more than one. If you are writing about one (for example the puppy's paw, then the apostrophe is indeed correct.) I am probably BU in letting it affect me so much but I just had to vent!