Initially, many early Christian congregations held two "services" a week. Sunday was a worship service open to all. Wednesday was a closed service to those with commitments to Christ. History does not really tell us what went on in the closed services, but the Bishop of Rome strongly suggested that congregations either stop the Wednesday services or open them up to all. Some historians think this "secrecy" helped fuel the misunderstanding you have described.
You know quite a bit about the Roman Empire and the early church. How did you get to know so much. I am impressed!
Always loved the Roman civilization. Received a degree in classics, many, many, many years ago. How did you come by studying the early Christians?