There is logic in your argument, however, you are missing one thing - restriction of human rights under Sharia.
IBB's money comes from Islamic religion and Sharia -- they promote it openly. Sharia in turn, coupled with government protection, is a totalitarian regime that puts a gun to people's head to force them to do certain things. So the product of their labor is not an output of a free market. And therefore, your argument does not apply.
To illustrate this point more dramatically imagine that I trick people to come to an island for a big opportunity. Once they arrive they find out that there is a factory that makes iPhones. I don't let them leave the island and I shoot anyone who tries to escape. I have food and shelter for them, but I will not pay them anything, and they are forced to work for me as slaves. Suppose food and shelter for these people costs me $1/day, while their labor in a free world would actually cost $100/day. The cost to make an iPhone would be $10 for me, while perhaps the cost to make an iPhone in regular conditions is 10 times as much. Of course I will be able to make a huge profit on those iPhones, so big that I will be able to give attractive loans. I will also use excess money to create a philosophy in which the slaves will not think of themselves as slaves, but more as those fighting for a higher cause -- a religion called Xyz, that demands 1 year of forced labor in order to achieve 1 year of bliss after death. People who will call me a liar I will label as confused souls that need forced guidance. I will advertise this philosophy as a new solace to happiness.
This example is not as far fetched as you might think. You can watch the movie "East-West" about a call to expat Russians to return to Soviet Union, under Stalin. They couldn't leave Russia afterwards, and were forced to work at a tenth of their income they would have in Western Europe, as well as, to live at one tenth the standard of life.
This kind of thing happens all over the place, in history, and even today. Forced-labour of people who are in jail (because they are against the government), cheap labor in China because of Govt import/export taxes and emmigration restrictions (Red China), tricking girls into prostitution (Zwi Migdal), and your plane old slavery. In fact, just by going through history, we can find the same kind of conflicts that exist today.
It is true that you can leave Iran today, although I imagine the process is not simple. But by the time you grow up to be an adult to make such a decision, you have already been taught about the world through the lens of Islam and Sharia. Even if you wanted to have an independent opinion during your childhood or teens, you couldn't have -- just try to say openly there something against Islam. You would be be torn to pieces.
The same was happening in Russia. People were afraid to say something in their kitchen that is against the government. The walls had ears. Also, when there was a parade, everyone had to come out -- if you don't, people will report you. After Stalin was dead, people finally started to speak, still very slowly.
In order to have a free market, people must be free to do for work whatever they want, and where they want. If they want to create a travel agency for American girls in mini-skirts to visit Tehran, they should be free to do so. And citizens of Tehran should be free to look at those girls, at the risk of loosing some friends (but not their heads).
This point of view comes naturally if you understand the source of human rights. Why do I think I have a right to start such a travel agency ? The answer is here:
http://www.theobjectivestandard.com/issues/2011-fall/ayn-rand-theory-rights.asp