Stewardship is this crazy idea that we should treat other people's stuff better than our own. To me, stewardship is the act of taking care of something you were given whether or not you could acquire it for yourself in the first place. It's less of an environmental idea and more of a common courtesy, which is exactly what stewardship should be, common. That's not to say the planet isn't involved in it, I mean I plan on living on Earth for a while.
I don't know about the rest of you. Anything that is handed to us, especially free of cost, should be treated with more respect than we give to our own possessions.