You might already have suspected that the reason why you engage in a fierce, almost Hunger Gamesesque competition to stow your carry-on is because no one wants to pay to check bags. That free-for-all has resulted in U.S. airlines making less money off baggage fees for the first time since they started assessing them.

The Transportation Department said yesterday that the 17 largest airlines made $3.36 billion in bag fees last year, which is a bit of a decrease from $3.4 billion in 2010, according to the Associated Press (via Washington Post).

Meanwhile, the total number of passengers went up by about 2.4% — which means even more overstuffed overhead bins and restless waiting during the boarding process to scurry onboard as soon as possible.

Fees for checked bags began four years ago when fuel prices hit an all-time high. Before that, many airlines already charged for heavy or oversized bags. Since then airlines have collected increasing revenues for checked bags — between 2008 and 2009, for example, money from bag fees rose by 42%.

So who’s made the biggest payload from checked bag fees? Delta, with $863.8 million collected last year. That’s more than the second largest carrier made in net income. American grabbed $593.5 million in fees last year, a year when its parent company AMR Corp. lost $2 billion.

One might wonder if Spirit made a big chunk of change, as they’re currently the only airline to charge for carry-on bags. They came in eighth on the list, with just $134 collected in fees. JetBlue doesn’t charge for the first checked bag, and as such only brought in $64 million. It has almost four times the traffic of Spirit.

Airlines collect less revenue from checked bag fees in 2011 for the first time [Washington Post/Associated Press]

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