Keep in mind that we're in Argentina, a land of price controls and big possible penalties if you break them. What incentive does anyone on a black market have to pay more for a dollar right now? It's not a product that cost someone to produce, so the value is what the government says it is, more or less. When they have a few people bitching and moaning about the low price, all the arbolitos have to do is point to the cuevas and blame it on them, while the cuevas point to the government and blame it on them. It's not much different than a monopoly where everyone has decided to keep a price at an artificial high, certainly not a freer market where supply and demand is the biggest deal.
A real black market wouldn't be able to compete with the price controls in this case because demand isn't strong enough to overcome the government's threatened force and besides, they would be the only ones charging lower prices and they would fail.
It's different when the government puts a price control on real manufactured products that have a specific overhead (for example) - people will go through bigger hoops to make money off of their investment in real stock (i.e., figure out a way around price controls) than in a currency black market where you're performing arbitrage anyway, not holding or producing inventory and freaking out about watching its real value fall every day. For profits, there is a lot more wiggle room in the blue market, currently.
Keep in mind I didn't say that supply and demand has nothing to do with it. But it is not as big a factor as when people can still make a profit without going to jail or having their business shut down, or getting tagged by AFIP, and thereby getting into real trouble. The market is not big enough, nor is the demand high enough, to drive heavier risk and break out of the government's desired price control on this commodity, is what I think.
Now, if inflation all the sudden blooms out of control, the demand for dollars would probably rise quite a bit and I think we would see a different story. Pretty much everyone that can would be looking to buy dollars with their pesos in order to have more stability at that point. Demand would outstrip risk and I don't think the government would be able to control the price and it would be a more free market truly driven by supply and demand. It's one thing being able to put your finger in a hole in the dike, but when you have more holes than fingers, you can't hold the flood back.
As strange as are the decisions this government makes, I'm betting they have tried to find a relative "sweet spot" in which to keep down the blue rate, based on how they see things going through to the end of the year, after the elections choose the next president.
