There is a lot of negative press about airlines overbooking flights and bumping passengers. As a budget traveller who often has flexibility with her itinerary (I often don’t even book accommodations or plan where I am going until I arrive) voluntarily giving up my seat has resulted in flight credits to feed my travel addiction on several occasions. There are entire websites dedicated to figuring out how to book on a flight most likely to be oversold, and people who are able to travel completely free by taking advantage of these opportunities on a regular basis. I am not this organized but have been lucky enough to get bumped on a few occasions. The airline will provide you with food vouchers, accommodations (if necessary) and a voucher for future travel. When you hear the announcement calling for volunteers, always inquire as to what the revised flight plan and compensation are. When I went to Ecuador, I got a $500 travel credit with United Airlines and arrived home only 45 minutes later than my originally scheduled flight. Getting bumped off a flight in San Francisco resulted in staying in one of the nicest Hilton hotels I’ve been to, better than my bed at home and a $350 flight credit. I remember a friend declining a bump because she had already booked and paid for her hotel in a stopover city, not realizing the airline would have put her up in an equally as nice (if not better) hotel, free meals, AND provided her with several hundred dollars’ worth of flight credits for future travel. Since she was only connecting through this town and catching another flight the following day, this bump would have actually saved her the trips to and from the airport at this stopover.
Because I live near a major international airport, I have the flexibility of knowing I can take many different routes to get home. If you live somewhere less serviced by major airlines, taking the bump may not be as beneficial to you as a delay on one end could cost you a day on the other if your home airport only has one flight/day and you miss that connection.