Why do childfree women feel the need to say this? The underlying message is that if you don't like children, you're a bad person. I don't believe that. And I'm tired of the apologetics. You can be a good person and not like children.
I don't like children - or more specifically, badly behaved children. I'm indifferent to well behaved children.
It's more about the lack of manners than the age of the person. I don't like rude people, no matter what their age. Children above the age of 5 are capable of behaving themselves in public. When they don't, it's more an issue of not being taught manners than it is about "kids being kids".