I couldn't attend a child free wedding because I was BF'ing my baby.
Babies under the age of 6 months (including formula fed babies) were allowed in but babies over that age weren't. My DS was 6 months and two weeks so was told I couldn't bring him. The groom was a very close friend of my DH's and I knew the bride really well, but they still wouldn't let me bring DS even though they knew he was BF.
They obviously thought that when a baby hits six months of age they go from being EBF the previous day to then miraculously changing overnight to having 3 meals a day and taking bottles when thirsty.
As a result our friendship pretty much came to an end. It was pretty difficult when all the wedding photos came out and there were lots of bottle fed babies there but my breast fed one was allowed.
My husband was really upset over the whole thing and he didn't go to the wedding either.
We really didn't mind the fact it was 'child free' but my husband was very disappointed that his friend wouldn't make an allowance for our BF baby because he was 2 weeks over the cut off point.
I do understand the concept though of if you make allowances for one you have to make allowances for others etc and then where would it end? So I can see their point of view to a degree but it got awkward and messy.
It's been 10 months since their wedding and we haven't even seen them since. That certainly isn't because we are avoiding them but I think they feel uncomfortable about it all.
The way DH and I saw it was that if we were getting married and a really good friend of ours was breast feeding there's absolutely no way I would tell her that her baby isn't welcome. I would never jeopardise her attendance just because she had a baby, it would be ludicrous. I think we all judge others on the actions we would take and I guess it taught us that my DH probably wasn't as good a friend to the groom as he thought he was. We both know the decision came from his Bridezilla fiancé though.
Anyway OP - you have the right to make any decisions around your wedding but as has been said, if you exclude babies then there's a good chance you are excluding their parents too. You just need to ask yourself if it's really worth it and in the grand scheme if things, does it really matter if a baby is there if it isn't actually going to cost you anything?