It’s just human nature. It’s not a bad thing, but it *is* something that we really need to wrap our heads around.
When we make predictions regarding the consumption or saving of resources, they always seem to be straight-line, single factor predictions. Yet time and again we see that, when you make things more efficient people will find new and innovative uses for them that will ultimately either wash out the savings or end up consuming greater quantities thereof.
In a book that I read back in October of 2006, “The Bottomless Well: The Twilight of Fuel, the Virtue of Waste, and Why We Will Never Run Out of Energy“ by Peter Huber & Mark Miles they argue this theory quite convincingly.
It was with some amusement then, that I read this article in “thecarconnection.com” (Hybrid Drivers More Ticket- and Accident-Prone) where, in establishing the context for the article they point out that recreational (read “discretionary”) driving by hybrid owners is about 25% greater than by non-hybrid owners.
I’m not sure if this would be because folks who drive more tend to buy hybrids or if it’s that folks who drive hybrids tend to rationalize extra driving due to their reduced per-mile fuel consumption. The reality is probably a combination of those factors plus others that I haven’t even considered.
The reality is that human psychology is not easily predictable and you can pretty much guarantee that you *can’t* guarantee what effects changes in policy or technology will have when you have people involved in the mix. And any artificial influences (legislation) had better be crafted in such a way as to be able to accommodate that reality and respond flexibly when the unintended consequences do eventually manifest.