The Hidden Cost of Charging for Luggage
About a year ago Delta Airlines made a decision to start charging for luggage. The plan was simple. $15/bag for suitcases under 50 lbs and a $90 surcharge for bags over 50 lbs. Delta ran the numbers and figured out it would be an easy way to drive additional revenue. Their research probably showed that the only thing people really care about is the price of the ticket, and it was probably further rationalized by the fact most trips are short enough that a carry-on bag can suffice. Charging for bags would make flights more profitable, but it would also have consequences.
The biggest consequence of this decision was expected. Delta knew customers would be upset when they had to pay $15 for baggage, so I'm not going to focus on that. What's more interesting are the consequences they didn't plan for.
A $90 surcharge on bags over 50 lbs is an extremely large fee. It's potentially a 1/3 or more of the total ticket price. Naturally people will want to avoid this fee. However, the 50 lbs mark is right at the upper limit of what a large bag would weigh, so a large number of customers will carry bags that are 51-55 lbs (especially for couples who share a single bag), and the majority of customers who encounter this fee will be barely over the "limit." These customers will try to do anything to avoid a fee of this magnitude. In fact, many customers start to unpack their luggage while it's sitting on the scale in order to try and get below the arbitrary 50 lbs limit.
The question now becomes, how much longer does delta spend interacting with each of these angry customers unpacking their bags at the check-in counter to avoid the $90 fee? A normal bag drop-off takes a minute, maybe two minutes. Each customer who unpacks their bag at drop-off to avoid the fee will generally take 7-10 minutes. One customer now takes the same amount of time to deal with as 3 used to. This an efficiency cost, and it won't be offset since the overweight baggage fee goes uncollected.
The other unintended consequence of this decision is that it encourages people to use larger carry-on bags. This means more bags must now fit in the carry-on compartments. Boarding is no longer about getting people to their seats, it's about finding space for all the carry-ons. Instead of preparing for take-off, flight attendants spend 10-15 minutes moving and re-packing carry-on compartments.
It's not that Delta doesn't understand behavioral economics, they do. And, it's not that they didn't carefully study this decisions, they did. They just failed to account for the unintended consequences. They were so focused on the potential increase in top line revenue that they ignored the hidden costs associated with it.