The complexity can go much deeper ... if they let it. That is, if they really let their spreadsheet nerds run wild. How about charging more to ride on Splash Mountain which is a great ride at any time, but MUCH more to ride it between 11am and 5pm, and MUCH MUCH more to ride it anytime on a statutory holiday ... than to visit Hall of the Presidents. This is simple market logic and it is indisputably more fair. Likewise, why do MK and DHS cost the same?
Given that a great park like MK has an imbalance between 5 or 6 great rides and a lot of really old ... um .. classics ... and an imbalance between the perceived quality and entertainment value of their entire parks, the only fair thing is to crunch the numbers and find out how much your customers will pay to either ride or avoid certain attractions and parks.
Or, Disney could try harder to make the theme park experience even and fair by upgrading parks, upgrading attractions, adding attractions, balancing opening hours, and so on, in order to maintain a simple price structure but also ensure approximately equal guest experience no matter which park is visited on any day of the year. And relatively stable profit levels year round. That would be fair, it would be perceived as being fair by their customers, and we wouldn't be having this debate.
But they're clearly going down the path of greater complexity, by offering unbalanced, unequal experiences for unequal amounts of money. And the motivation isn't "to ensure a better guest experience", it's because of financial priorities which have something to do with keeping capital expenditures to an absolute minimum. Unless the capex involves condominiums or conglomerations of franchise stores and restaurants (what some would call a glorified strip mall).