Why ever pay to leave a dangerous area? Just wait until Uncle Sam comes to the rescue and gives you a free ride.
Good way to end up dead and not exactly fair in this case.
Very likely that most of these people had a ticket back to the States but because the airport, port and roads are closed they were unable to use them. It's not as if they lost all their money in a poker game and went to the consulate begging for a free ride back to the States. (Yes that does happen!)
There is literally no safe way for them to get out except this way.