Some Christians are Christians in name only. They love the idea of being a Christian, but have no clue how to be one. I imagine that happens with people who belong to any religion.
Don't apologize for telling these nasty women how rude they were and bluntly questioning their Christianity. Seems to me that they needed someone to give them a good kick in the butt. Would have loved to have seen their faces when you told them what they really are!
Who knows? You might have gotten a few of them to realize how un-Christian they were behaving. Doubtful, but it could happen!