Friends of mine, one of whom is agnostic and the other some kind of Christian (she flops around a lot, but was baptized in the RC), recently got their child baptized in a Roman Catholic church. The godfather is an atheist. I don't know the godmother so I can't say where her faith lies (or lack thereof). I have no they managed to convince the priest this was a good idea. I did not attend because I felt the whole ceremony was just a mockery of the sacrament. I believe there was some family pressure to have the little girl baptized which is probably what happens in a lot of these cases.
When my wife and I were going through pre-Cana classes, the deacon leading the seminar asked, "Why are you getting married in a Catholic church?" and most of the responses were, "It's tradition...it's just what we do in our family...blah blah." Most were taken aback when I answered, "Being with someone else is hard enough without having the grace of God to help you out."