The Lord's Supper: A Christian Thanksgiving
Someone may have communicated something like the following to Paul:
“When the church was gathered at so-and-so’s house for the Lord’s Supper, they had their best friends (other richer families of the church) with them in the triclinium (dining room) where all the food was served (and where some were even getting drunk as in a common drinking party). The rest hung around out in the atrium and hardly got to eat or drink anything. It was apparent from where and what each one was served (if anything) how they ranked in terms of their social status.