And, from an earlier post the membership has to do with things like speaking into the Church's decision making, correct?
I think this is one of the problems with the institutional model of the Church that somehow took over the relational model of the New Testament. I'm not enough of an historian to know when the change occurred but I am daily confronted with the issues a congregation faces when it owns property, pays staff, funds programs, and all the other activities involved in institutional Christianity.
I don't mean to deny the value of structure to a fellowship, just identify the difficulties when that fellowship becomes an institution.
Have you heard of the Plymouth Brethren? They have a different model that is intentionally no more than what is found in the bible. The word pastor is hardly used but there is a lot about elders so they are more elder focused. Most elders are laymen. They keep away from debt and have almost no one on the payroll.