The airlines reported $14,816,370,067 in ancillary fee revenue for the period July 2011 - June 2012. Ancillary fees include baggage fee, extra legroom, premium seat selection and on-board food and services. This averages about $50 per passenger on Quantas, $34 on Allegiant, and $23 on Flybe. The bulk of this is of course checked bag fees.
Representatives at JFK Airport say that one of the best selling items in the airport is luggage. People pack too much into their one suitcase and are over the weight limit. It's often cheaper to check two lighter bags than one heavy bag.
The airlines change fees fairly regularly and if you're like us, looking for the lowest fare, and with no allegiance to any airline, meaning no gold/platinum status, you're going to pay something for a checked bags. If you regularly check bags, are the type to purchase a ticket for a $50 saving,s think about what the airline is charging for a checked bag before you click the purchase button.
We like to go to the website below from Fare Compare. It does a very good job of going into specifics on baggage fees and allowances.. They also include details on several int'l airlines. This page was updated on Jan. 25th.