The simple truth is that when people book flights, they buy the cheapest fare going where they want to go when they want to go. In that world, the only incentive is for the airlines to cram more people onto each plane and add fees. I was just on American, and they show a low fare, but then you discover that it's only available for middle seats. Aisle or window seats were "premium" and charged more. If you want to sit with your spouse, you had to cough up the money.
This can all be blamed on Emirates Airlines and their design input due to the 150 777 they have on order. Helps bring more Jihadi’s to the USA