Brokers match people with a surplus of miles with people who want miles.
Sorry, no Midwest Airline Center Event tickets are available at this time. Some major cities have three or more airports, and not all discount flights will take you to or from the most central ones. Brokers match people with a surplus of miles with people who want miles. Know which airports you'll be using, especially if you have connecting flights. The broker obviously makes a profit by selling miles for more than he or she pays for them.