[derefr]

> "Reducing" is the least expensive because it doesn't require any energy, but we (consumers) like to buy stuff, so once a product is in a person's hands, "reduce" is out of the equation.

From a commercial perspective, "reducing" isn't about "reducing" the purchase of marketed goods, but rather reducing the waste/pollution/etc. that goes into manufacturing those goods. Like reducing plastic wrapping on boxes, etc.