Common Law Church

I've recently been considering the purpose of church membership. My first membership experience, which happened during college, left a bad taste in my mouth. From today's Boundless article "Common Law Church":

I taught fourth-grade Sunday school at the church for two years. Because the church had thousands of members, the only person who really knew me was the Sunday school superintendent, who met with me monthly. At the end of my service, I graduated from college and moved away. I called the church and explained that I would no longer be a member due to geographic location.

Though I've lived in Colorado for six years, my parents continue to receive mail from this church. After repeated attempts to dis-member myself, I finally gave up. As a result, I viewed membership as an exercise, involving the signing of a doctrinal statement and indelible induction into a database.

Consequently, I was leery of becoming a member at my new church. Because I committed at the level of a member (attended regularly, led a small group, tithed), I didn't see a reason to sign a piece of paper and make it official. After talking with Pastor Mark Dever at New Attitude, I am reconsidering my position. Is it possible that committing to church without that final, binding step of formal membership is a bit like a common law marriage? What does the Body of Christ lose in this scenario? How is my attitude toward the church affected?

The article leaves these questions hanging, but I hope Dever's extreme stance that membership is a biblical mandate will provoke thought. Do you think he has grounds for his conclusion? Are there spiritual benefits only membership can offer? Why is this idea so appealing to our generation?