Visiting a theme park shouldn't be more complex than doing taxes.
Its not... and your tax comment is a great analogy.
You can pick up TurboTax or TaxAct or FreeFile and do your taxes for free. Completely legal, very easy, done in an evening. Did you get the MAXIMUM value out of doing your taxes? Did you get every penny? How many "billions" did you leave on the table? Don't know... but it was painless and easy and free and you did the necessary activity.
Or... you can follow the "advice" of the TV ads, and the accountants, and the paid services. You can spend a year planning, save every receipt, meet every deductible, contribute to charities for the sole purpose of dropping your tax burden by 2%, replace your window to get the tax credit, make every decision to maximize your credits. Then take all that paperwork, all those records, and go to an accountant and run the numbers and review the options and maximize your tax return.
There are people who will tell you that you are nuts for not doing the 2nd option. You gave up hundreds or thousands of dollars to the government who is just going to use it to buy fancy toilet paper and you are a fool.
Its your choice to believe the hype, do the planning, make the decision, pay the accountant, and get every penny back you are due. Or, you know, spend 2 hours one evening in February, get back 95% of what you would've gotten back anyways, and call it a day without the burden and stress.
Same with Disney. If you didn't plan 1 single bit, woke up Tuesday morning, decided you wanted to go to Magic Kingdom that day, you could get Fastpasses for everything you wanted EXCEPT 7DMT and Anna & Elsa. So get your 3 fast passes day of, go to the park, enjoy it, and stand in line for 7DMT for 70 minutes instead of 5, and A&E for 60 minutes instead of 10. But if the thought that other people "planned" their day 2 months prior and stood in line for about 2 hours less and did the same things you did upsets you... I'm not sure anyone can help with that conflict. The option is there, and if you don't use it nothing is taken away and hopefully you are happy with the choices.