I still occasionally run into license holders who think you can't carry into church, either because (i) was not properly explained to them* or they've forgotten it. In conversations with one of the elders of our church he mentioned being told by a local police detective that the church didn't have to post because carry in churches was prohibit.
*At the instructor class, the slides that DPS uses on this are ...inadequate... The state something like "Carry in church is prohibited" and then in smaller print below "must be posted in accordance with PC30". After the instructor covered that I heard someone behind me ask his neighbor "so you still can't carry in church?"