Even as I preach on this topic and guide these discussions, I'm learning things. That's one of the blessings of being a pastor, that as you help to teach others, you may grow as well. One of the things that I've come to realize in this process is this: As God makes us good stewards, God is liberating us from the bondage of our culture. Check out this video that helps to put a visual image to this teaching.
That's the key. The identity of a steward is wrapped up in the care for and distribution of someone else's goods. Royal stewards care for the kingdom in the absence of the monarch, using the resources of the crown. In the same way, as stewards of God's creation, we are called to care for creation as the Body of Christ here on earth. The stuff that we have at our disposal is not ours, but Christ's. This identity as stewards of God's Kingdom liberates us from the burdens of our culture and frees us to become images of God, witnessing to the grace we've received.