Heh, all the work in that comment is in the "just" in the last sentence. You can sort of see it as an extension of the efficient markets hypothesis: if there w

Heh, all the work in that comment is in the "just" in the last sentence. You can sort of see it as an extension of the efficient markets hypothesis: if there were money lying on the ground, someone would already have picked it up. Alternative formulation: any kind of arbitrage, whether in terms of the stock market or in terms of allocating labor to an underserved need, has to have some kind of search costs to it.