I’m one of the few that likes all these fees. Whenever something is free people just waste it, and mass/volume on an airplane is limited. And I’d rather have my base ticket price lower and opt in to fees for stuff that I actually value.
1. Lack of clarity. I've no problems paying a fee I want and use. But when the fees are hidden at point of sale, and then added later it makes comparisons hard or fees I don't want getting added because I didn't know about them in advance so couldn't change behaviour to avoid them.
2. Fees that don't accurately capture the benefit Vs the cost, and are gamed. Things like "2 peices of hand luggage" with no weight specified. I once had an attendant tell my wife her hat she was carrying counted as one peice, so she had to put in her bag to walk past the check-in desk to avoid being charged a fee for extra hand luggage. And then you get the opposite with schemes like wearing vests to carry extra items without it counting in your hand luggage allowance. I once had to move ~2kg from my hold luggage to my hand luggage because one was over and the other under. Why not literally charge a per kg fee regardless where you store it that way everyone pays for exactly what they use, no gaming. The current fee structure tends to incentivise maxing out on hand luggage to avoid hold fees, which means overhead storage gets crammed full. Charging per kg would shift a portion of this to the hold and make the cabin less cramped and better for everyone.
I travel with a laptop, portable monitor, iPad pro, switch, GoPro, moonlander keyboard, mouse, bunch of plug adapters and a multiway extension. All of that adds up to 9kg when you include the bag base weight.
One time when I was flying from Istanbul to Mauritius, they weighed the bag and it was a big headache. Eventually someone else came along and just let me on since it was all battery powered stuff that couldn't go in the hold.
Charging by weight doesn't make more room in the overhead storage though. Going by volume does, and many airlines do check volume. Especially in Europe, I've seen Ryanair and easyJet stop people many times.
If you look on Amazon, you'll see entire ranges of bags optimized for Ryanair free carry-on limits.
Of course some people don't understand how capitalism and competition work and therefore don't trust that the base prices are lower than they would be otherwise. But that's just not understanding how the economics of the industry works.
I'm very happy to restrict myself to a carry-on and not have to subsidize people bringing large checked luggage.
I fly regularly and with wildly different luggage configuration. I want to pay for what I use, not less and not more. Sometimes I fly only with hand luggage. Once I flew with 6 suitcases totaling 160 kilos from Dubai to Zürich.
What I want are customizable options with clear prices. Frequently it’s only possible to add more than one suitcase over the phone…
The problem is if for a specific route or airport there's only one airline. That seems to be somewhat common in the US, and in that case price isn't constrained by competition but the customers willingness to pay. That's where the abusive practises flourish
It’s not enough data to attribute the impact of the broad switchover to baggage fees in 2008-2010, as base prices actually went up after introduction, but base prices are definitely down over time.