I agree with Jennifer that 'conscious consumption' leads to greater satisfaction. If we can fall in love with one useful artifact and get value and pleasure out of it for a long time then we may not need a pile of other "cheap things."
In extending our notions of sustainable design beyond rethinking how we we make things we can also focus on the services that people desire instead of the product in itself. Consumer needs may be inexhaustible but what if they can be filled, even if it is temporarily, without creating so much waste, with an emphasis on producer responsibility and still generate income?
I've been reading a bit about the business case for sustainability, CC. I found good info in: Natural Capitalism and a talk by Bob Willard - his books address sustainability through risk management and asset management. - JN