I stopped going to church when I was seven years old. DH was a member of his church's choir but gave up at thirteen and neither of us had set foot in a church since then (apart from the usual family occasions). We weren't married in church as I was divorced - first wedding wasn't a church wedding either. I considered myself a Christian in the sense of believing in God, but didn't really see why I needed to go to church to do that.
But, when DS came along and survived a heart procedure when he was a couple of weeks old, we felt we wanted to celebrate that and we honestly felt something/someone had watched over him because of the number of coincidences that had happened to save his life. I know it sounds daft, but that's what it felt like.
We spoke to our local vicar and were honest with him about the fact that we felt uncomfortable about standing up in church and pretending that we'd attend regularly in order to bring our son up 'in faith' but that we felt the need to say 'thank you' to someone (or something).
The vicar told us about a ceremony of thanksgiving and blessing which you can have in a CofE church - it's a halfway house where you have a blessing, say prayers and have hymns but without the promise to attend church or even to bring your child up in any sort of religion. Plus you could nominate special people to act as Godparents in all but name (you only have Godparents if you're Christened).
So we decided to do that. In fact we were the first in our parish to have that ceremony and the vicar asked us to do a piece about it for the parish magazine. He's done quite a few since then as it's very popular - allows for the 'show' of christening without the commitment.
We were so happy with the way the vicar helped us even though we were making no promises to him that we now go to church once a month, on family days, so that our son can make an informed decision about whether he wants to be part of the church when he grows up. If he wants to be baptised when he grows up that's fine; if it's not for him that's OK too.
I don't have a problem with people who have kids christened then never attend church (a lot of my friends have done exactly that) but there are alternatives if, like us, christening felt a step too far, too fast.