Hiro, I honestly don't mean to be rude here, but are you ABSOLUTELY sure you know what you're talking about? I mean, the mechanism to allow us pay land fees in Lindens is hardly eating up hundreds of gigabytes of storage on the SL servers.

Suggesting that because YOU wouldn't use it doesn't mean that it's not used, or that having the developers invest the time to remove it completely would be at all practical, well... that's silly.

Yes, I agree that it would be ill-advised to choose to pay one's land fees that way, but presumably, SOMEONE uses it. Besides, there's a reason the Lindens set such a low number -- it's a money sink. Without drains on the economy, the world would continue to fill up. Think about it, there's hundreds of new users every week, with weekly stipends and signup bonuses and all kinds of money coming INTO the system, but it doesn't GO anywhere. As Lordfly correctly points out, to use market rates to pay land fees could very quickly exhaust the supply of Lindens, driving the cost up even higher. Now, I wouldn't totally have a problem with that, but I suspect most of my customers and clients would.
That's why there are Linden products for sale. The Lindens aren't doing it as a secondary source of revenue, they're doing it to drain money out of the economy. You have to remember, the Linden dollar is not inherently valuble, nor is it not a backed currency. Linden Lab doesn't make any money by minting them -- they're worthless. The only reason people assign value to it is because there's demand for it.
This is the same reason they have land auctions payable in Lindens -- it's a money sink. If land bought at auction was simply recycled back into the economy, we'd get inflation. That's the whole point of having money sinks.
Now, whether or not the high demand for Lindens is directly caused by the scapegoat of the week (as Cashmere suggests) is another matter altogether. To assert that the sole driving factor in the SL economy is the sale of land is kind of a simplistic look at the system. The SL economy is a lot more complex than that. For instance, my income is based almost entirely on selling scripts, yet I'm making more money than I suspect many of the residents who've been labeled "land barons" make. I've had plenty of people ask for a script, and then go directly to GOM to get the cash to pay me. A couple people have paid me directly via Paypal. (I'll also accept payment in the form of SL land, cash and computer hardware.

)
My point is that the SL economy is vastly more diverse than most people realize. The biggest moneymakers aren't land speculators, they're clothing, animation and script makers. The demand for Lindens isn't simply driven by land prices.
For that matter, land prices aren't even the direct result of the actions of these horrible, horrible land barons. They're the result of the Lindens releasing too few sims.