I get where the OP is going. Some child-free people. and it is a small group, do go on about how being child free means they can go where they want, do what they want, have so much more money because they are not tied down by children, but then acquire pets, which to my mind are far more of a tie than children and often for much longer and they seem to end up spending as much on the pet than one would on child.
As I said, these are a small group of attention seekers, just looking for online attention and there are such attention seekers all over the place.
I do not think the OP is referring to the majority of childless people, whether childless by choice or, so to speak, having it thrust upon them for numberless reason. Just those who crow over being childless, while their lives are run round their cats, dogs or what other animal they favour.