I have not read the all the other responses...but here is my take on being a member of a church.
I am Baptist...I was saved a little over 12 years ago and baptized in the church were I accepted Christ. That made me a member of that church. A few years later I began to attend a different Baptist church closer to my home and my son's school. During the invitational I went to the Pastor and asked to have my Baptismal certificate transferred to the church. That made me a member of that church.
I am now on my third church - having moved again. And just a few weeks ago, after attending the church on and off for year, once again made the trip to the alter during the invitational and became a member of the church.
You are not asked to be a member of the church, through your request, either through initial salvation or by asking for your baptismal certificate to be transferred you become a member of the church. Just attending the same church does not make you a member. Your name must be placed on the church roles and your baptismal certificate must be transferred to the church.
That is the concrete explanation of membership to a Baptist church.
The abstract concept of church membership will vary from person to person. I believe that is a feeling of being part of a "family". Developing friendships with people within the church, knowing that in a time of crisis they will help you and you will help them. Bringing a dish to the Sunday potluck, and joining a ladies night out. A lot of what you get out of church membership is what you put into it. If you are only going to services then leaving, you will not achieve a sense of membership. It is not wrong to just go to services - it is a personal choice.
As to the "money talk" - churches have mortgages, utilities, Pastor salaries, and other bills to pay. Tithing and donating to the church, asides from being biblical, help support the church and keep its doors open so that you can receive Word of God. I am currently in between jobs and my income has been cut 75%, but I still tithe. Why? Because I have seen my tithe returned to me 100fold. Concrete example....I received a call from a creditor - it seems I had overpaid them(they overcharged me) and they wanted to refund my overpayment...it exactly equaled the amount I have tithed over the last 2 Sundays.
M., churches are like doctors - you want to find one you are comfortable with. If you are not happy with the church you are attending, visit other ones until you find one that is the right fit for you and your family. Don't deny yourself and your family the joys of church membership - this may just not be the right church for you.
Remember, churches are run by people with all the inherent failings that we have - look past that and to the Word of God and you will make the decision that is best for your family.
God Bless.