There is also less likely to be a connection to the Body of Christ throughout the world in a non-denominational movement. Through the denomination, one can be involved in organized relief efforts, missionary efforts, support of schools, hospitals, seminaries and nursing homes. As we gather around the communion table, we are gathering with Christians around the world at the table of our Lord. Brothers and Sisters in the Lord. When they are also fellow Lutheran Christians, that conection seems even stronger.
Denominations also help keep the theology on path.
Where as there is considerable latitude when it comes to the freedom of each individual pastor or congregation, when connected to a denomination, a congregation is less likely to become shanghaied by some nut from the religious right. Connected to a group, there is some accountability, and this is good. I can see where one could see denominations as necessary evils in those denominations where a power elite exercises control rather than healthy support, opportunity and guidance. I remember a Bible text study for pastors in West Union Iowa which was attended by ELCA Lutheran, Methodists, Weslyan, Presbyterian, Catholic, Lutheran Brethren, 4-Square Gospel and occasionally a Baptists. The only one who had a problem was the LCMS pastor who would park behind my garage and come in the back door to the church because if his district supervisor finds out he is at the Bible study he would be out of a call That kind of control is not good.