Child free weddings shouldn't even be a thing.
It's not like children are a different species - these are people who will grow up and be part of the lives of the bride and groom in the future. Whoever started the idea that it should be a normal thing - it's wierd!
Fine if you don't want to take your children, but to actually say to people they cannot come is awful awful awful, and people fall out, forever, over the difference in opinion - which could never possibly be resolved as once a couple have decide they are not inviting children they get all defensive and convince themselves it's perfectly fine, normal, standard behaviour to exclude people, important people, family and friends from your wedding, of all things, based only on their age.
What's next - granny-free weddings? nobody over the age of 50? It's just as arbitrary. And discriminatory.
Of course, I have no previous experience in this area, nor have i ever been excluded from my best 'friends' wedding as I had a five month old who couldn't be left, and was not permitted to attend. ahem
And I haven't spoken to her since