I accidently exposed part of my holster one day before Mass. One of our priests saw it. He was very positive about my concealed carrying. I know of another member of the parish who also CCs. She is one of the leading members of the parish. Outside of that priest and our spouses, no one else knows that we carry. There could be other CCers in the congregation. I am not interested in knowing who they might be.
We live in a suburb of Chicago outside of the Chicago Archdiocese. Fortunately when Illinois passed CC, there was no mention in the bill concerning carrying in houses of worship.