> Whereas, in reality, it's only a question of what a buyer will pay and what a seller will accept.
I didn't say that's not what determines a price.
> When you look at an airline that's about to fly a plane with twenty empty seats, do you say "sheesh, it's totally unreasonable that seat is selling for anything more than zero, it costs the airline nothing to have someone sit in it, the greed is mind-blowing"?
No. Plane tickets are quite cheap regardless when you consider the amount of force involved in lifting that much weight into the air across the planet. Even when it's more expensive, I'm saving a ton of time compared to if I drove my car across country and back, making even pricier tickets worth it. In fact, the way I look at it, a plane with a bunch of empty seats is a good thing because that allows people to make last-minute travel plans. If one had to reserve a plane ticket months in advance, that'd be pretty lousy.
So perhaps that was just a bad example.
Here's the flaw in your oversimplifying of the argument. The price being as simple as what the buyer is willing to pay for is only adequate when you ignore the seller's level of monopolism and the market incentives that drive the buyer to taking it in the rear. Apple not only dominates a massive percentage of the mobile phone market, but they along with Google have created systems where your digital service is unlikely to be successful unless you play their game... because they are oh so concerned about the safety of the end user. And app that's not found in the App Store is never going to reach widespread use because even Android users don't really want to use apps their friends who have iPhones can't interact with them on. Even if you host binaries on your own site, good luck having iOS users figure out how to side-load the app or even have the courage to do so.
Would you be fine if your bank just ripped off 1/3 of your income? After all, what are you gonna do? Use cash for everything and be closed off from the modern economy? Sure, you can do that. But does that mean that this hypothetical banking system isn't ripping you off regardless of if you choose to pay it? It's a large amount of value that the buyer earned that the seller arguably didn't earn. In the case of Apple, they effectively get a 30% share in every company that hosts an app in the App Store because at any moment Apple can just say "nah" and delete the app.
But sure... let's have a society where everything's a free-for-all and we don't regulate scams and ripoffs because the buyer was willing to pay for it.
EDIT: I now realized what I said was on the snarky side... I changed it but left some of it and hope you're not personally offended or anything.