Antenatal, as it suggests in the name, encompasses everything in the later stages in pregnancy leading up to and including labour. So that's why they're birth orientated
More beneficial would be a free parenting course instead of free antenatal classes IMO but the govt funds the AN ones.
As for coffee groups meeting once a week, if you haven't all had your babies, just wait until you have! I bet most people won't want to meet once a week for the first wee while. I personally prefer my coffee group (who I met through AN classes) every 2 weeks and then if we feel like catching up in between we do. Now that the kids are more active and we are a lot busier (some back at work full time, part time etc) once a week is too much of a commitment.