I'm just sitting here shaking my head. Apparently none of you have ever tried to put on a show. It costs money. Get over it. If you think you can rent a facility -or run your own, paying lights, insurance, rent, utilities, and permits- then go ahead, put on a show. Advertise it (oops, that costs money, too!), find jurors, make a budget, figure out how many people are going to participate and how much you're going to have to pay out for the jurors' expenses and stipends, the prizes (if any), and the aforementioned overhead of the venue, plus wine and food for the opening cocktail, and then just sit back and rake in the cash!! If you need help spending all that money, let me know!
I don't believe gallery owners in general are raking in the dough, nor do I have disagreement in principle with anyone making money. What I am trying to say is that all costs are self limiting in behavior. The market determines exactly what it will bear. Higher prices in good times, lower in bad or vice versa depending on exactly what the commodity is. There is no shortage of photographic art, but if there becomes a shortage of photographers willing to shell out to be in shows because they can't afford it, either the price will come down if there is enough margin to sustain a price reduction, or the venues will go away or find a different model because the structure isn't viable in the current economy. My guess is that there will be both. I suspect if the model of hanging photographs for free and charging admission were viable outside a museum, it would be in widespread practice.