My wife is heading to Ft. Worth today. She has taken only one carry-on bag because the airline has a fee for checking bags. This is an incentive to not check bags which I guess saves the airline fuel from less weight and manpower from reduced staffing of luggage crews.
Of course, the result is that everyone tries to jam in as much as they can into their carry-on bag... and the women have enormous purses as well... which leads to the inability to find space in overhead storage. Consequently, the flight crew must deal with congestion in the aisle as passengers attempt to shove their carry-on into a space smaller than their carry-on and finally the flight crew has to ask people to have their carry-on put in normal storage below... without paying the fee.
Southwest Airlines realizes that complicating the overall process like that is counter-productive... just to advertise a slightly lower ticket price. They allow two stored bags for no extra fee. Passenger loading is easier; travelers don't have to go through contortions with excess carry-ons.Unfortunately, today she in not flying Southwest.